Add some error-handling and logging to LDProject
Add some error-handling and logging to LDProject

We were seeing some System.InvalidCastException errors in the dev server
logs from LanguageDepotProject, so apparently some projects are missing
a sendReceiveProjectIdentifier. Add some code to catch that and, as a
first step towards solving the problem, report the problem in syslog.

sillsdev/LfMerge,ermshiperete/LfMerge,ermshiperete/LfMerge,sillsdev/LfMerge,ermshiperete/LfMerge,sillsdev/LfMerge