Fix path to datafiles

If distributed as egg, the generated path
should be /usr/share/python-keepass-httpd/conf/
Rename binary
Update README.md

Add basic setup and installtion instructions.
Use reStructuredText instead of Markdown

This makes it easier to publish this packages on PyPI.
Add publish_release to Makefile
Do not allow passwords in commandline

This could be a security vulnerability, so ask
the user while strating the server via prompt.

This fixes issue #1.