Fix packaging source optimization does not work for package builds

Moved all targets specific to the postbuild phase of the build into the postbuild ant file.

Created framework for separating postbuild related activities into a separate file.

Moved comments around to be adjacent to the thing that they're describing.

Added Build environment check feature

platform build temporary patch - overidden sf-build-noprep to not generate the model from the fragments. Needed for split model builds and furhter work on simplifying model.

catchup merge

BOM fix - Changed to reading project location ${sf.project.location} instead of ${sf.config.dir}/../build/config, which isn't always correct.

catchup merge

Smoketest change - Added 'sf-find-ATS-worker-root' to build.xml so that the smoketest goes where the worker is expecting it on a individual basis, rather than it being hardcoded to D:\ATS\...

ATS testing on emulator - Renamed properties for lon-engbuild87, lon-engbuild89, and sym-build02 so they are the same as the machine name. Modified the TEMPDIR for c100726 so that it runs smoketests

sf-list-dir - added new tool 'listdir.py' which can exclude a directory and changed the behaviour of sf-list-dir to stop scanning epoc32/build to speed things up.

sf-postbuild - running analysis in parallel with evalid and post-build zipping.

Merge

Simplify the create-canonical-sysdef-file target as we can depend on there only being a single sysdef in the supplied reference.