OmeroCpp: Syntax corrections
OmeroCpp: integration/search: Correct use of C macros and casts
OmeroCpp: Remove inappropriate and dangerous casting
OmeroCpp: DetailsI: Separate declaration and definition of methods to avoid warnings
OmeroCpp: integration/search: Correct undeclared functions and casts
OmeroCpp: don't declare unused variables in combined.vm
OmeroCpp: RTypesI: don't declare unused variables
OmeroCpp: PermissionsI: don't declare unused variables
OmeroCpp: integration/search: Correct casts in checks
Merge pull request #2951 from rleigh-dundee/cpp-fixes

OmeroCpp: Miscellaneous fixes