node: replace nullid and friends with nodeconstants class
The introduction of 256bit hashes require changes to nullid and other
constant magic values. Start pushing them down from repository and
revlog where sensible.
Differential Revision: https://phab.mercurial-scm.org/D9465
{
// 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)
}