Merge

Add Helium 7 support for package builds. - During operation, if last.major.helium.version is detected as 7.0 then it will use new sbsinput mechanism. - Restore sf-postbuild dependency on sf-build-noprep target

Added error correction, so if a cache repository is corrupted in some way, then it will by-pass it, and try to recover it, or delete it.

Moved definition of dollar, so it's available for use when needed.

Stopped cache being located/created in a stupid place, relative to the CWD on the cache drive. Work around limitation of ant-contrib regular expressions, so they're not thwarted by \s in the cache location property.

Add missing / Avoids potential problem of it not seeing an existing cache, depending on the CWD on the cache drive at the point the target is running (which could be anything really).

Turned on use of cache for all platform builds (unless over-ridden by the particular job properties of course).

Bug 1661: Simplified the sequence of pulls/clones via the cache, so the changes simply go from source -> cache -> destination. Made use of --uncompressed flag to speed things up. Including setting the flag when we create a cache entry.

Bug 1661: Improve build speed with better caching strategy Changed the way that the cache is located, so the same code can run on any build machine without any configuration. Made work around for Bug 419 the only option, as we're not using the alternative anyway, and I don't want to commit completely untested code! Changed caching algorithm, to improve build times.

Updated capabilities of findPhysicalDrive to support imminent work on locating the hg cache.