Fixed #831
Opera needs same special treatment as webkit for :checked selector
Added Benchmark.js v1.0.0
Added benchmarkjs's nano.jar
Added Benchmark.js license to library LICENSE.md
Tree: Massive speedup in Tree#emptyNode().

Previously, `emptyNode()` triggered a node map reindex for each node
that was removed. This commit modifies `emptyNode()` to remove nodes in
last-first order and avoids the need to reindex.

Previously, emptying a node with 10,000 children took about 17 seconds
in Chrome. After this change, it's nearly instantaneous.
Build tree.
Merge branch 'master' into benchmarkjs
YUI and Loader build for latest Gallery build
Add simple benchmarks for promises
Updated Promise perf tests to work in CI
Merge pull request #6 from derek/promise-bench

Updated Promise perf tests to work in CI
Delete old benchmarks
Update lang-test.js

Unit tests added to trim, trimLeft, and trimRight
Update yui-lang.js
Merge branch 'patch-4' of git://github.com/ziggyism/yui3 into dev-master
Update history.
Build yui.
Updated path to Benchmark.js for app, base, event-custom, node, tabview, and transition.  Also, updated async execution and logging of results to match the latest API.
Merge branch 'promise-bench' of github.com:juandopazo/yui3 into juandopazo-promise-bench
Merge branch 'fix831-opera-selector-checked' of git://github.com/asystance/yui3 into dev-master