PGClientKit for iOS Updates

- Updated project settings:
	- Added 32 bit to Architectures
	- Updated iOS-Universal-Framework scripts for PGClientKit_ios to use
latest mk8 version. The previous build scripts were failing when trying
to link all framework versions together. The new Python scripts works
great.
- added pg_config.h for PGClientKit_ios target.
- Updates to make-libpq.sh and make-openssl.sh build scripts to
reference systems gcc compiler.
- Corrected assertion firing when empty strings returned from PGRest in
-fetchRowAsArray