fix: add :enabled sub-config for fixer tools
This allows distributing opt-in fixer tool configurations in .hgrc
files. This may be useful for adding default configs in core, or for
orgranizations that want to provide configs to their users.
Tools are still enabled by default because it would be confusing to add a
config and find that it has no effect until you add enabled=true.
Differential Revision: https://phab.mercurial-scm.org/D6975
{
// 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)
}