Fix library not linking on simulator build (fix #62)

* In Xcode, setting GCC_ENABLE_OBJC_EXCEPTIONS = NO unexpectedly sets -fexceptions flag when compiling Objective-C++ for the simulator. This then requires linking to libc++.dylib. To avoid this, we set the exception flags directly in the OTHER_CFLAGS and OTHER_CPLUSPLUSFLAGS settings.
Ensure fileData is actually copied when reading uncompressed zip files

On pre-10.9 systems, [NSData copy] returns the same object, see rdar://14670403. Using [NSData dataWithBytes:length:] always creates a new object.

Create data objects using "alloc"/"init" instead of "data" to avoid autorelease pools not getting drained quickly.

Minor style fix.
Merge pull request #63 from goetzf/master

Fix memory corruption when reading uncompressed archives on pre-10.9 systems.
Merge commit 'f762c1ffcc4e9e6dde5f87570ee842683c42228e'

* commit 'f762c1ffcc4e9e6dde5f87570ee842683c42228e':
  Ensure fileData is actually copied when reading uncompressed zip files
  Fix library not linking on simulator build (fix #62)