Merge in resource performance improvements #2

Release Notes: resource performance improvements

fix a resource copy problem (not copying when multiple copies required) that showed up in the tests.

fixups: tests for resource improvements

fix: take action on copy tags at the end of build phases.

small resource fixes

fix: resource problem - horrible code that tries to produce different versions of the same resource - preevent file mixup in this case.

fix resource deps: generate more cleanly - no targets if there are no prereqs. no empty lines. fix resource copy performance: remove debug fix filters: behave if someone puts 2 identically named filters into the plugin dir by mistake.

fix performance: copy resources in the frontend. Helps cluster builds since remote copying is inefficient.

minimising dependencies might have helped after all by ecluding something that's getting updated that maybe shouldn't. Try it out again.

Merge

fix: use only one dependency file per resource - not one per language per resource. Speed improvement. fix: revert dependency minimisation (doesn't help, causes problems)

improve resource copying speed on certain clustered build systems by forcing them to happen locally.

allow recipestats to print hosts used in the build.