There are cases where the state of a SortIncludes object gets messed
up and leaks between invocations/files. This typically happens when a
file ends with an include block (dump_block() gets called at the end
of __call__). In this case, the state of the class is not reset
between files. This bug manifests itself as ghost includes that leak
between files when applying the style hooks.
This changeset adds a reset at the beginning of the __call__ method
which ensures that the class is always in a clean state when
processing a new file.
I didn't realize that the perl version existed when I started this,
this version has a lot more features than the previous one since it will
sort and separate python, system, and m5 headers in separate groups, it
will remove duplicates, it will also convert c headers to stl headers
