Updated gitignore to exclude compile

One of the automake files “compile” was missing from the exclusions
list.
Fix compiler warnings about missing enums

PBArray value type functions should not be the container for
objective-C objects.  We use native NSArrays for this purpose in the
generated code.
Fixed prefix header include.
Merge branch 'master' into gen-modern-objc
Fixed unit tests for runtime library.

Framework search path property must be specified for SenTestingKit to
work.
Implemented NSENUM support for enum

NSENUM has special editor support for parameter completion in
objective-C.  Any valid 32 bit integer, negative numbers are
discouraged but possible, may be used as input in google protocol
buffers enum syntax so NSInteger has been chosen as the type.
Use the package name as the class prefix

Protocol buffer syntax “package <name>;” can be used a prefix to
objective-c classes.  Its a convenient namespacing syntax that
translates well between C++ and Objective-C.
Removed errors and warnings from generated code

To remove some of the warnings, a few values have been boxed with objc
literal expressions.  Most of the work has been done on the compiler.
Object Subscripting, Boxed Expressions

The compiler now generates code that uses Object Subscripting for array
element access and Boxed Expressions when creating temporary NSNumber
objects (used in description formatting and hashing).
Merge branch 'gen-modern-objc'