Expose XxxReference comparisons

[atykhyy]

Re issue #389.

[AnakinRaW]

what's holding this one back from merging @jbevain ?

[jbevain]

@AnakinSklavenwalker comparing metadata elements is tricky, and not everybody will want to do exactly the same thing, I'm not very excited about providing a public API that would become the source of truth for is a TypeReference equal to another TypeReference.

[AnakinRaW]

fair enough. Would you be OK having the comparer into the Rocks project. This way it can be documented that this might not be a 100% correct implementation, (according to the ECMA spec) but it works for most cases. Since I need such a comparer for my project anyway, i could create a new PR which re-implements the feature and puts it into Rocks.