Pass options object to parser.parse in less.render.
Merge pull request #1921 from rback/master

Pass options object to parser.parse in less.render
Eat up comments instead of calling them parse error:
* in @keyframe declaration #2059,
* after rule name before semicolon #826.

The comments are eaten instead of being printed into output, but it is
better then crashing on them.
tt
Merge pull request #2169 from SomMeri/comments-keyframe-rule

Accept comments in @keyframe and after rule name - merging for next patch release.
Fix property interpolation for `@*` values
Merge pull request #2173 from seven-phases-max/master

Property interpolation fix for `@*` values
Merge remote-tracking branch 'origin/master' into 2_0_0

Conflicts:
	lib/less/index.js
	lib/less/parser/parser.js
	lib/less/tree/rule.js
	test/less/property-name-interp.less