When JUnit tests have assumption failures, treat them as "skipped"

JUnit has a conception of "assumptions", when encode conditions in which a test is meaningful.
When an assumption fails, it means that the test provides no useful information, and should
"halt and be ignored".  Prior to this change, Gradle was treating JUnit tests with assumption
failures as "passed".

http://junit.sourceforge.net/javadoc/org/junit/Assume.html
Add unit test coverage for JUnit assumption handling
Add integration test coverage for JUnit assumption handling
Made notify-send notifications transient so that they don't clutter notification panel in Gnome Shell
Added (broken, ignored) test that demonstrates issue with resolving parent pom with SNAPSHOT version
GRADLE-2642 - Changed InMemoryIndexedCache to use the provided serializer.
GRADLE-2641 - Some hackery to handle parent POMs with SNAPSHOT version. Needs a deeper reworking of parsing to fix properly.
Add more integration test coverage for Html reports for TestNG
- cover forkEvery and maxParallelForks
- introduce HtmlTestExecutionResult to verify test results against html report
Merge pull request #115 from erdi/notify-send-transient

Make notify-send notifications transient
GRADLE-1620: support testng tests declared by o.t.a.Factory annotation.
GRADLE-2645 Bugfix in maven conversion (bootstrap plugin).

Removal of xml element is now smarter. MavenProjectXmlWriter class is really a temp until we finally start walking the maven object model when converting (we already have the model - it's implemented).
Removed some code from CompositeStoppable that we don't really need.
fix failing ci
Merge pull request 114 (treat tests with assumption failures as skipped)
Mention latest merged pull requests in release notes.
Some spec updates.
Merge branch 'release'
Updated build to use rc-2
Some more updates to distributions spec.
Added a spec for fixing GRADLE-2649 and generally handling suites better.