Remove --harmony implications for incomplete features

Remove --harmony implications for incomplete features

This is in preparation for making --harmony and --es-staging synonyms.
The only remaining difference currently is block-scoping, which is still
implied by --harmony, to avoid regressing on a long-available feature.

Also removes the special-casing of --harmony-proxies.

R=adamk@chromium.org
BUG=

Committed: https://code.google.com/p/v8/source/detail?r=25115

[adamk, 2014-11-03 17:50:04]

lgtm

I also like the "INPROGRESS" tag, much better than what blink calls this
("experimental"). This makes it clear that such features aren't supposed to be
working yet.

[rossberg, 2014-11-04 16:05:38]

Committed patchset #1 manually as 25115 (presubmit successful).