fix(limitTo): do not convert Infinity to NaN

parseInt(Infinity, 10) will result in NaN, which becomes undesirable when the expected behaviour is
to return the entire input.

I believe this is possibly useful as a way to toggle input limiting based on certain factors.

Closes #6771
Closes #7118
fix($compile): reference correct directive name in ctreq error

Previously, ctreq would possibly reference the incorrect directive name,
due to relying on a directiveName living outside of the closure which
throws the exception, which can change before the call is ever made.

This change saves the current value of directiveName as a property of
the link function, which prevents this from occurring.

Closes #7062
Closes #7067
feat(ngModelOptions): support submit trigger