[CB-1285] initial commit of exif header writer source, with appropriate license, migrated from incubator repo
[CB-1285] removed dead code in implementation, fixed xcode warnings, commented
Merge remote-tracking branch 'upstream/master' into CB-1285
[CB-1285] added support for additional metadata provided by camera in iOS updates, tested and refined rational approximation algorith, added support for additional datatypes
[CB-1285] added unit tests for CDVJpegHeaderWriter, tests rational approximation and utility functions involved in the creation of the APP1 data block in a JPEG header. For test of APP1 data block integrity, best method is to read resulting image
Merge remote-tracking branch 'upstream/master' into CB-1285

merging upstream changes into local branch
[CB-1285] readded public helper functions supporting splice into existing jpeg nsdata operation
[CB-1285] added exif binary string splice operation to camera jpeg case, removed auto header
[CB-1285] replaced debugging copy (per byte) with block copy in data splice, removed logging
[CB-1285] uncrustify and added project files to pbxproj
[CB-1285] fixed unsued var warning, and incomplete implementation warning
[commenting] removed xcode auto header block
Merge branch 'refs/heads/CB-1285'