Create README.md
No decimal point in the SDLVER
Remove copyright lines and the LICENSE file.

These will be replaced with a new version that refers to an AUTHORS
file. The AUTHORS file approach is far superior, as you can add an
author by simply adding a line to one file, instead of fixing all of
the comments.
Add new copyright lines to source files, LICENSE file, and AUTHORS file.

Fixes #11
Merge pull request #20 from eaburns/dev/license

Change author and license info to refer to an AUTHORS file.
Rename .hgignore to .gitignore.

Otherwise git status is useless.
Make ensuredir more general.
Fix a typo in a comment.
Add more serialization/deserialization functions.
Add save().
Add load, and some small fixes to save to match.

They are ugly at the moment, but I tested a few times and they work.