Adding Yard Tags into a template (#20)

Yard object have tags linked to them

https://rubydoc.info/gems/yard/file/docs/TagsArch.md

These tags contain a lot of useful information - returned type, accepted attributes, deprecation notices, links to more documentation and etc. 

It's a pity that yard-markdown doesn't include that information, this is a PR that resolves that. I'm going through all possible tags that CodeObject has associated and adding them to output.

## Technical part
I added `example_yard.rb` file that we can use to generate yard example, that has these yard tags. `example.rb` go renamed to `example_rdoc.rb` to align with this naming.

---------

Co-authored-by: Stanislav (Stas) Katkov <github@skatkov.com>

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    yard-markdown (0.3.6)
+    yard-markdown (0.4)
       csv
       yard
 

README.md

@@ -31,4 +31,8 @@ This is a successor to [rdoc-mardown gem](https://github.com/skatkov/rdoc-markdo
 ## Testing
 Unit tests can't really test this gem properly. So it's semi-manual process of making changes and reviewing output.
 
-  `yardoc example.rb` -> outputs everything into example/ folder.
+Testing Rdoc conversion to markdown:
+  `yardoc example_rdoc.rb` -> outputs everything into example/ folder.
+
+Testing Yard conversion to markdown:
+  `yardoc example_yard.rb` -> outputs everything into example/ folder.

example/Aquatic.md

@@ -0,0 +1,20 @@
+# Module: Aquatic
+
+**Defined in:** example_yard.rb
+
+A mixin for aquatic creatures.
+
+# Public Instance Methods
+## swim() [](#method-i-swim)
+Swim in the water.
+
+**return** [void] 
+
+
+# Constants
+## DEFAULT_SALMON_SPEED [](#constant-DEFAULT_SALMON_SPEED)
+
+
+## MAX_DEPTH [](#constant-MAX_DEPTH)
+
+

example/Fish.md

@@ -0,0 +1,35 @@
+# Class: Fish
+**Inherits:** Object
+
+**Defined in:** example_yard.rb
+
+The base class for all fish.
+
+# Public Instance Methods
+## make_sound() [](#method-i-make_sound)
+Make a sound.
+
+**return** [void] 
+**yield** [sound] The sound produced by the fish
+**yieldparam** [String] The actual sound
+## swim(direction, speed) [](#method-i-swim)
+Swim in a specific direction.
+
+Swimming is the most critical feature of fish.
+
+**param** [Symbol, String] The direction to swim
+**param** [Integer] The speed at which to swim
+**return** [Boolean] Whether the swim was successful
+
+**example**
+```ruby
+swim(:north, 30)
+```
+
+# Constants
+## DEFAULT_SALMON_SPEED [](#constant-DEFAULT_SALMON_SPEED)
+
+
+## MAX_DEPTH [](#constant-MAX_DEPTH)
+
+

example/Salmon.md

@@ -0,0 +1,58 @@
+# Class: Salmon
+**Inherits:** Fish
+
+**Includes:** Aquatic
+
+**Defined in:** example_yard.rb
+
+A salmon is an Aquatic Fish.
+
+## Features
+
+*   **Fish**
+    *   make_sound
+    *   swim
+*   **Aquatic**
+    *   swim (overridden)
+
+# Public Instance Methods
+## initialize(farmed, wild) [](#method-i-initialize)
+Creates a new salmon.
+
+**param** [Boolean] Whether the salmon is farmed
+**param** [Boolean] Whether the salmon is wild
+**return** [Salmon] a new instance of Salmon
+## make_sound() [](#method-i-make_sound)
+Salmon overrides generic implementation.
+
+**return** [void] 
+**yield** [sound] The sound produced by the salmon
+**yieldparam** [String] The actual sound
+## sustainable?() [](#method-i-sustainable?)
+Checks if this salmon is sustainable.
+
+**return** [Boolean] Whether the salmon is sustainable
+## swim() [](#method-i-swim)
+Swim in the water.
+
+**return** [void] 
+
+# Public Class Methods
+## wild_salmon() [](#method-c-wild_salmon)
+**return** [Array<Salmon>] List of all wild salmon
+
+# Attributes
+## farmed[RW] [](#attribute-i-farmed)
+
+**return** [Boolean] True for farmed salmon
+## wild[RW] [](#attribute-i-wild)
+
+**return** [Boolean] True for wild salmon
+
+# Constants
+## DEFAULT_SALMON_SPEED [](#constant-DEFAULT_SALMON_SPEED)
+
+
+## MAX_DEPTH [](#constant-MAX_DEPTH)
+
+

example/index.csv

@@ -1,21 +1,20 @@
 name,type,path
-Waterfowl,Module,Waterfowl.md
-Waterfowl#DEFAULT_DUCK_VELOCITY,Constant,Waterfowl.md#constant-DEFAULT_DUCK_VELOCITY
-Waterfowl#DEFAULT_SPEED,Constant,Waterfowl.md#constant-DEFAULT_SPEED
-Waterfowl.swim,Method,Waterfowl.md#method-i-swim
-Bird,Class,Bird.md
-Bird#DEFAULT_DUCK_VELOCITY,Constant,Bird.md#constant-DEFAULT_DUCK_VELOCITY
-Bird#DEFAULT_SPEED,Constant,Bird.md#constant-DEFAULT_SPEED
-Bird._fly_impl,Method,Bird.md#method-i-_fly_impl
-Bird.fly,Method,Bird.md#method-i-fly
-Bird.speak,Method,Bird.md#method-i-speak
-Duck,Class,Duck.md
-Duck#DEFAULT_DUCK_VELOCITY,Constant,Duck.md#constant-DEFAULT_DUCK_VELOCITY
-Duck#DEFAULT_SPEED,Constant,Duck.md#constant-DEFAULT_SPEED
-Duck.initialize,Method,Duck.md#method-i-initialize
-Duck.speak,Method,Duck.md#method-i-speak
-Duck.swim,Method,Duck.md#method-i-swim
-Duck.useful?,Method,Duck.md#method-i-useful?
-Duck.rubber_ducks,Method,Duck.md#method-c-rubber_ducks
-domestic,Attribute,Duck.md#attribute-i-domestic
-rubber,Attribute,Duck.md#attribute-i-rubber
+Aquatic,Module,Aquatic.md
+Aquatic.DEFAULT_SALMON_SPEED,Constant,Aquatic.md#constant-DEFAULT_SALMON_SPEED
+Aquatic.MAX_DEPTH,Constant,Aquatic.md#constant-MAX_DEPTH
+Aquatic.swim,Method,Aquatic.md#method-i-swim
+Fish,Class,Fish.md
+Fish.DEFAULT_SALMON_SPEED,Constant,Fish.md#constant-DEFAULT_SALMON_SPEED
+Fish.MAX_DEPTH,Constant,Fish.md#constant-MAX_DEPTH
+Fish.make_sound,Method,Fish.md#method-i-make_sound
+Fish.swim,Method,Fish.md#method-i-swim
+Salmon,Class,Salmon.md
+Salmon.DEFAULT_SALMON_SPEED,Constant,Salmon.md#constant-DEFAULT_SALMON_SPEED
+Salmon.MAX_DEPTH,Constant,Salmon.md#constant-MAX_DEPTH
+Salmon.initialize,Method,Salmon.md#method-i-initialize
+Salmon.make_sound,Method,Salmon.md#method-i-make_sound
+Salmon.sustainable?,Method,Salmon.md#method-i-sustainable?
+Salmon.swim,Method,Salmon.md#method-i-swim
+Salmon.wild_salmon,Method,Salmon.md#method-c-wild_salmon
+farmed,Attribute,Salmon.md#attribute-i-farmed
+wild,Attribute,Salmon.md#attribute-i-wild