Revert "Remove path.existsSync as part of node 0.8 minimum environment"

This reverts commit 1b740375f2cd02af466acab8e481d5b4fc79297c.
Merge branch 'dev-master' into dev-3.x
Adding HISTORY for #949
Merge branch 'dev-master' into dev-3.x
Merge branch 'dev-3.x' of git://github.com/yui/yui3 into dev-3.x
Add empty functional tests for automation.
Merge branch 'dev-3.x' of github.com:yui/yui3 into dev-3.x
Fix RGB Slider test.
fix flaky recordset indexer functional test by adding click listener
Fix case sensitivity problem on Promise functional tests
Merge pull request #991 from clarle/func-test-fixes

Functional test fixes for Promise
Merge branch 'dev-3.x' of git://github.com/yui/yui3 into dev-3.x