MSRPC SCons tool:
*Allow for providing a .acf file as one of the sources. The builder will now make sure that /acf is inserted before each .acf that appears in the resulting commandline. We use an action generator to do this.
*The build emitter was accidentilly using the first source file as the base for all target names. It now uses the first target if it exists, else it falls back to the first source.
