Add better autocomplete support (#14)

* WIP: Add better autocomplete support

Use inner classes to offer better autocomplete support. The inner
classes only expose methods that are valid at any point in the fluent
api chain.

* Remove unused methods and variables

These methods were being used to ensure the methods are called in the
right order. We no longer need these since we are using inner classes.

* Remove redundant inner class instances

* Make inner class constructors private

* Remove unused message

* Adding final to several inner class properties (#13)

* Change inner classes' naming scheme

Name inner classes '_Entry','_Midway' and '_Exit'. Not thrilled about
the naming scheme but rolling out with this for now. Could possibly
change later, but won't affect the api.

* Change UM apex class version to 53.0

Co-authored-by: James Simone <16430727+jamessimone@users.noreply.github.com>

config/project-scratch-def.json

@@ -6,11 +6,6 @@
     "lightningExperienceSettings": {
         "enableS1DesktopEnabled": true
     },
-    "securitySettings": {
-        "passwordPolicies": {
-            "enableSetPasswordInApi": true
-        }
-    },
     "mobileSettings": {
         "enableS1EncryptedStoragePref2": false
     }