Add .py extension to dbdownload
Migrate to setuptools

distutils to setuptools migration allows transparent/platform-independent
binary handling (also on Windows).
Fix OS path and timezone issues

- Path building should have been more OS-independent;
- File modification time should take local timezone in account;
- Add example .conf file.
Update README.md
Merge pull request #3 from the-happy-hippo/master

DBdownload platform-independent fixes