Janet 1.14.2

This patch release fixes some bugs with the ev/module and adds preliminary support for ev/thread, which can spawn and wait for threads without blocking the event loop. Communicating with threads should still be done with os/pipe.

• Allow JANET_PROFILE env variable to load a profile before loading the repl.
• Update tracev macro to allow def and var inside to work as expected.
• Use (dyn :peg-grammar) for passing a default grammar to peg/compile instead of loading
  default-peg-grammar directly from the root environment.
• Add ev/thread for combining threading with the event loop.
• Add ev/do-thread to make ev/thread easier to use.
• Automatically set supervisor channel in net/accept-loop and net/server correctly.