Added support for files referred to by the main file.

We simply output all of them.
Fixed compiler warnings.

Function that are not used but may be still interesting were attributed
the "unused" flag.
Write out the context related code to dedicated buffers.

Before we simply wrote it out via cout. This change allows the
write out the context related code into separate files.
Fixed the type of the context parameter for functions without args.
Precede all output with the file names.