FMDB.h should be public in the FMDB-IOS target as well

FMDB.h was not being included in the FMDB-IOS target.  Also
FMDatabaseAdditions.h and FMDatabaseQueue.h, included by FMDB.h,
were not marked public in the FMDB and FMDB-IOS targets.
Merge pull request #4 from inkling/golden/misc_fixes

FMDB.h should be public in the FMDB-IOS target as well