[ELPA] Package proposal: relint (ex-trawl)

[Mattias Engdegård]

This is a proposal to add relint, an elisp regexp linter, to GNU ELPA.

Relint, previously called trawl, has been used to pester this list with regexp 
errors. Adding it to ELPA may make it more available to Emacs users who write 
their own elisp code.

Relint currently resides at https://github.com/mattiase/relint and is proposed 
as an external ELPA package.

The plan is still to integrate it with Emacs `make check' in some way, unless 
the developers dislike Makefile rules that use locally-installed external 
packages. It will not be mandatory.