Implemented statistics for Crawljax.

Fixes #314
Also add the metrics to the crawl session
Fixed bug with injection the registry
Fixed the tests.
Fixed typo
Updated the release notes
Fixed Javadoc
Fixed minor issues
[maven-release-plugin] prepare release crawljax-3.2
[maven-release-plugin] prepare for next development iteration
add crawlpath in CrawlerContext to use it from plugins
add crawlpath in CrawlerContext to use an immutable copy of crawlpath from plugins
remove blank (no-text) javadocs
Merge pull request #324 from daisy1754/refactoring/remove-blank-javadocs

remove blank (no-text) javadocs
Merge pull request #321 from Juntostics/master

add crawlpath in CrawlerContext to use it from plugins
PhantomJSDriver support added.
add the largeTest for PhantomJSDriver
Merge pull request #327 from crawljax/phantomjsdriver

PhantomJSDriver support added.
Fixed dependency hierarchy for phantom JS
Updated Phantom JS