.jshintrc

rebase: change and standarize template for rebase's one-line summary

This removes the default template in rebase and switches to a
centrally defined template. I've simplified it a bit to avoid the
conditional parenthesis. I've also added labels so the different parts
can be easily colored. The template is somewhat similar to what we've
used internally at Google for a few years.

I'm happy to change the template if others have opinions. Should we
reuse the `color.log.` names as I have?

Differential Revision: https://phab.mercurial-scm.org/D9252

{
    // Enforcing
    "eqeqeq"        : true,     // true: Require triple equals (===) for comparison
    "forin"         : true,     // true: Require filtering for..in loops with obj.hasOwnProperty()
    "freeze"        : true,     // true: prohibits overwriting prototypes of native objects such as Array, Date etc.
    "nonbsp"        : true,     // true: Prohibit "non-breaking whitespace" characters.
    "undef"         : true,     // true: Require all non-global variables to be declared (prevents global leaks)

    // Environments
    "browser"       : true      // Web Browser (window, document, etc)
}