Replaced all URLs with URIs

The URL class is slow and broken. This commit replaces all the
occurences of URL that have something to do with the network. URL is
still used for file resources but that's ok.

Fixes #322
Fixed broken test.

Also set Git version to a less verbose version.
Also upgraded minimum Maven version to 3.1 to force modern plugins
Updated logback and jetty
Merge pull request #370 from crawljax/fix/322-url-to-uri

Replaced all URLs with URIs