xsd-fu: Extend C++ support

· Add GUARD property for include guards
· Add SOURCE_TYPE to distinguish between source and header output
· Source paths are relative to the output directory; this is to
  enable include guard generation
· Metadata output is a single target, rather than five separate
  targets
xsd-fu: Remove invalid git references from Java templates

Now the generated sources are not committed, these references
are invalid and unnecessary.
Updating copyright dates
Merge pull request #499 from qidane/in-steps-bf

Code changes for new schema
Merge pull request #513 from rleigh-dundee/xsd-fu-template-remove-gitref

xsd-fu: Remove invalid git references from Java templates
merge develop -D org -I include -E exclude: PR 506 (Memoizer: use Location instead of File to represent 'id')
merge develop -D org -I include -E exclude: PR 510 (CellomicsReader: Improve performance of initFile (develop))
merge develop -D org -I include -E exclude: PR 512 (xsd-fu: Extend C++ support to generate headers and include guards)