This change adds a master id to each request object which can be
used identify every device in the system that is capable of issuing a request.
This is part of the way to removing the numCpus+1 stats in the cache and
replacing them with the master ids. This is one of a series of changes
that make way for the stats output to be changed to python.
Adaptations to make gem5 compile and run on OSX 10.7.2, with a stock
gcc 4.2.1 and the remaining dependencies from macports, i.e. python
2.7,.2 swig 2.0.4, mercurial 2.0. The changes include an adaptation of
the SConstruct to handle non-library linker flags, and Darwin-specific
code to find the memory usage of gem5. A number of Ruby files relied
on ambigious uint (without the 32 suffix) which caused compilation
errors.