chore(*): enable jshint eqeqeq

[Narretz]

Add jshint eqeqeq and eqnull rules, and fix all resulting errors.

[Narretz]

@lgalfaso So, in parse there's actually a comparison that seems to be == / != on purpose:

angular.js/src/ng/parse.js

Lines 1532 to 1543 in aa077e8

	'binary==': function(left, right, context) {
	return function(scope, locals, assign, inputs) {
	var arg = left(scope, locals, assign, inputs) == right(scope, locals, assign, inputs);
	return context ? {value: arg} : arg;
	};
	},
	'binary!=': function(left, right, context) {
	return function(scope, locals, assign, inputs) {
	var arg = left(scope, locals, assign, inputs) != right(scope, locals, assign, inputs);
	return context ? {value: arg} : arg;
	};
	},

Changing == to === for binary== makes this expectation fail:

angular.js/test/ng/parseSpec.js

Line 1741 in aa077e8

expect(scope.$eval("1==true")).toBeTruthy();

, changing != to !== for binary!= does not. Can you take a look at this?

[gkalpak]

Seems like we are missing a test, e.g. expect(scope.$eval('1!="1"')).toBeFalsy().
Obviously we need to retain the ==/!= for binary== and binary!=.

[Narretz]

That's right, thanks @gkalpak