Add visitor.js array-based function cache for faster lookups. perf / #1615
Optimize visitor.visitArray() for perf. #1615
Misc. perf optimizations. #1615
New input chunker in parser.js. #1615
Minor fixes. #1615
Merge branch 'perf-tune' of https://github.com/fredburger/less.js

Conflicts:
	lib/less/to-css-visitor.js
fix tests
some code review changes and test for the new extra/missing parens check
test parens false negative
jshint: eval option
jshint: boss