Add windows-related temporary files to .gitignore

[whiteknight]

The windows build creates a number of temporary and intermediate files that are not covered by .gitignore. I would have modified that file myself, but it appears to be generated by mk_manifest_and_skip.pl, which I don't know how to modify and use for this purpose.

The files that need to be ignored typically end with .obj, .rc and .res. Here is the list I am seeing:

# Untracked files:
#   (use "git add <file>..." to include in what will be committed)
#
#	frontend/parrot/main.obj
#	frontend/parrot_debugger/main.obj
#	frontend/pbc_dump/main.obj
#	frontend/pbc_dump/packdump.obj
#	frontend/pbc_merge/main.obj
#	include/parrot/platform.h
#	include/parrot/platform_limits.h
#	ops2c.rc
#	ops2c.res
#	parrot-nqp.rc
#	parrot-nqp.res
#	parrot_config.rc
#	parrot_config.res
#	parrot_nci_thunk_gen.rc
#	parrot_nci_thunk_gen.res
#	src/embed/api.obj
#	src/embed/pmc.obj
#	src/embed/strings.obj
#	src/interp/inter_cb.obj
#	src/interp/inter_create.obj
#	src/interp/inter_misc.obj
#	src/platform.c
#	status.txt

[cotto]

whiteknight added these in b87413ecf2. I'm marking this as fixed.