[Java.Intreop] Rename Dispose methods

[radekdoulik]

These have different signatures than the common dispose pattern
methods, thus rename them to avoid confusion.

Catched by gendarme's
https://github.com/spouliot/gendarme/wiki/Gendarme.Rules.Design.UseCorrectDisposeSignaturesRule(2.10)

[jonpryor]

As mentioned on our last call, if we're going to rename JniValueManager.Dispose(IJavaPeerable) to JniValueManager.DisposePeer(IJavaPeerable), then we should also append a Peer suffix all the other verbs for consistency within JniValueManager, e.g.

• Add(IJavaPeerable) becomes AddPeer(IJavaPeerable)
• Remove(IJavaPeerable) becomes RemovePeer(IJavaPeerable)
• Finalize(IJavaPeerable) becomes FinalizePeer(IJavaPeerable)
• etc.

Thus, a question: which is "better", Add()/Remove()/Finalize()/etc. or AddPeer()/RemovePeer()/FinalizePeer()/etc.? If we don't like the Peer suffix, we should just ignore the Dispose() warning in Gendarme.

[radekdoulik]

Indeed, I misremembered it as belonging to another fix. Updated.

[jonpryor]

We should also rename Collect() to CollectPeers().

[radekdoulik]

Updated.