fixed integration tests which were breaking in non-clean builds

https://www.pivotaltracker.com/story/show/69740244 (HTTP API Module fails when not installed with clean)

This PR contains:

1) A fix for HTTP API Module tests that were failing when the build was run with `mvn install` instead of `mvn clean install` (this was mostly a case of not using the getRandomUniquePid() method, of the parent AbstractResourceIT class, to generate pids).

2) A similar fix for tests in fcrepo-auth-common (which could be seen to fail once the fcrepo-http-api tests had been fixed).

3) Code reformatting for the touched tests (lines allowed at 120 characters now, instead of 80), fixes in indentation (which will conform to checkstyle rules (once tests are run against them)), etc.

4) Removal of imports which weren't being used (Eclipse does this automagically when it does the normal reformatting).

5) Addition of a getRandomUniquePid() method in the AbstractResourceIT class in the fcrepo-auth-common package (similar to the AbstractResourceIT class in the fcrepo-http-api package) and a preference for using that method in the parent class rather than each test calling UUID directly.

All packages are building now with: `mvn install`