CSS: Add test for uri inside declaration
CSS: Fix `uri` node
Modify API

– gonzales.srcToAST() -> gonzales.parse()
– gonzales.astToString() -> gonzales.toString()
– gonzales.astToSrc() -> gonzales.stringify()
Move errors related code to a separate module
Refactor `lib/parse.js`

gonzales.parse(options) -> gonzales.parse(css, options)
Tests: Rearrange + add test for parsing error
Tests: Refactor parser tests
nani introduce nodes
Tests: Add Closure Compiler version of css syntax

Conflicts:
	test/bench.js
Tests: Use Benchmark.js for bench tests
nani closure advanced
node