Support builds using cx_Freeze to generate executables
Cleaner method for detecting cx_freeze
setup.py: bump version to 0.9+ while between releases
trailer.py: reformat to 4-char indent
Merge branch 'pr18'
update_files: add MANIFEST.in lines for versioneer.py and _version.py

This replaces the manual instructions to update MANIFEST.in, since it's
easy to miss, and the consequences of leaving versioneer.py out of
MANIFEST.in is that things work fine from a source checkout, but not
from a 'setup.py sdist' -generated tarball, which generally breaks pip.
Addresses issue #20.
test_git: ignore versioneer.pyc, if present
test_git.py: ignore `__pycache__` too
Make sure generated files get into MANIFEST.in
rename 'setup.py update_files' to 'setup.py versioneer'

"update_files" was too generic: the "setup.py --help-commands" output
didn't suggest that this command was related to Versioneer at all.

Closes #23.
release 0.10
setup.py: bump version to 0.10+ while between releases
start rearranging code to enable multiple VCS systems
split middle.py into from_keywords.py and from_vcs.py
rename "variable" to "keyword", makes more sense that way
rename parentdir to from-parentdir, for consistency
remove START/END from the long-version template

I think this was a leftover from an era when long-version.py had some
extra code that didn't go into the generated _version.py . At this
point, the whole thing goes in, so we can add the triple-quotes from the
outside.
split trailer.py into from_file.py, get_versions.py, and cmdclass.py
header.py: add notes
remove workaround for py2.5 missing os.path.relpath