Adding support for restoring fixtures between tests

Added helpers/venus-fixture class to handle caching and restoring venus-fixtures between tests
Made some changes to lib/executor, using process.nextTick in place of setTimeout, split out some
callbacks into functions with comments.

Updated .venus/adaptors to include the new venus-fixture helper cache/restoring.
Update .venus/config to include the venus-fixture helper in various configs.
sync with upstream
Removing binary screenshot
Merge branch 'master' of https://github.com/rbakr/venus.js

* 'master' of https://github.com/rbakr/venus.js:
  Adding support for restoring fixtures between tests
Fixing custom route issue from previous commit.
able to generate documentation via docker
Merge pull request #191 from roelrz/docker

Generate documentation via Docker
Merge pull request #187 from rbakr/master

Adding support for restoring fixutres.
Merge branch 'master' of github.com:linkedin/venus.js

* 'master' of github.com:linkedin/venus.js:
  able to generate documentation via docker
  Fixing custom route issue from previous commit.
Fix for issue_192, update selenium api
Merge pull request #193 from sethmcl/issue_192

Fix for issue #192 -- simplifying selenium API
Fixes for issue #194
Fixes for issue #194

We now use ip address instead of hostname for generating test urls.

You can now also manually override the hostname used, either on the command-line with the new `--hostname foo.com` flag, or through the config file with the `hostname` top level property.
Merge remote branch 'origin/issue_194' into issue_194

* origin/issue_194:
  Fixes for issue #194

Conflicts:
	lib/constants.js
	lib/executor.js
	test/specs/constants.spec.js
Merge pull request #196 from sethmcl/issue_194

Issue 194
Fix for eth0 failure on travis
Merge pull request #197 from sethmcl/issue_194

Fix for eth0 failure on travis
Changing syntax to specify selenium browser version
Merge pull request #199 from sethmcl/issue_192

Changing syntax to specify selenium browser version
Mocha & IE bug fix

In IE, the mocha library was executing tests before we could register to listen for the test result events.
Thus, our adaptor was not getting notified of the test results. Had to hack the mocha library a bit. Will investigate more
and see if this is a general bug in mocha that we should report.