Literate flag

Add `-L` or `--literate` command line flags (lowercase `l` is already taken) to allow literate coffee script to be read in from `stdio`
Fixes #2908, add "\n" between pure literal header and function body.
Fix error reporting for invalid object key
Keep the js comment on a single line if the herecomment is on a single line.
Merge pull request #2925 from marchaefner/master

Fix error reporting for invalid object key.
Merge pull request #2929 from lucasb-eyer/master

Keep a single-line herecomment as a single-line js comment.
Fix missing `` ` `` - #2926
Fix bug in REPL where history file was closed late.

The history file was set to close on process exit, when it
should close on REPL exit. Listening to the process exit
event causes a warning when more than 10 CoffeeScript REPL
instances are opened in the same program, which happens in
the test.
Merge pull request #2943 from bobbydavid/master

fix warning in REPL tests about memory leak.
Merge pull request #2940 from jiangmiao/issue2908

Fixes #2908, add "\n" between pure literal header and function body.
Fix #2944
Fix REPL when env.HOME isn't available - #2945
Merge pull request #2946 from Nami-Doc/issue2944

Fix #2944
Fix #1437. Unneeded ref in existential assignment.
Merge pull request #2951 from xixixao/issue1437

Fix #1437. Unneeded ref in existential assignment.
give the `-l` flag to literate

remove `-l` from lint, allowing it to be used for literate
Merge pull request #2894 from billymoon/master

Literate flag
remove --lint. #2894 : rebuild and fix docs
Fix docs : modify source file instead of built file
Merge pull request #2963 from Nami-Doc/lint-flag-removal

Lint flag removal