Clean up any wrapper download temp files that may be there because of a simultaneous download by another process.
GRADLE-2699 - use filesystem locks to prevent concurrent wrapper downloads interfering with each other during the unpack step.

Test coverage is inadequate at this stage.
Remove the incubating section from the release notes template and the 1.6 notes.
Build with Gradle 1.5-rc-1
GRADLE-2699 - Bump up our maximum size threshold for the wrapper jar to accommodate the multi process safety code.
GRADLE-2699 - Close all handles to lock files used to make wrapper installation multi process safe before trying to delete them.
GRADLE-2699 - release notes for multi process safe wrapper install.
Fix for tooling API + really old provider versions + ibm jvm 5
Use the supplied user home dir before converting command-line options.
Added some coverage for cyclic project dependencies.
Don't use a remote repo for these cross version int tests, as they use an isolated user home dir.
ported test to spock
more test coverage for DefaultPolymorphicDomainObjectContainer
fixed test
Added toString representations to assist with debugging
REVIEW-1737, REVIEW-1738: Improved exception handling for DeferredConfigurable
- Don't assume extension is missing if it throws UnknownDomainObjectException in configureNow()
- Rethrow configure exception on every access to deferred configurable extension
- Discard actions once they are used to permit garbage collection
Fix integ tests for new exception handling
REVIEW-1738: Ensure that all DeferredConfigurable extensions are configured (late) during project evaluation
- Added a ProjectEvaluator that gets/configures all DeferredConfigurable extensions after the main project evaluation
   - Added ExtensionContainer.getAsMap() to make this easy (configure-on-access)
- Wrap deferred configuration exceptions in GradleScriptException so that there's no difference between failure
  during regular script evaluation and deferred configuration.
REVIEW-1750: Improve test coverage
REVIEW-1755: More test coverage for custom source sets with builder tasks