Minor update to xls export with report

Just a minor update for xls report export: The format for cats2 was slightly different to what I expected; this is a fix for that. Now, not hh:mm format is used, but e.g. 10,5 hours, since cats wants it this way.

first public build

First public build. Expect this to contain bugs, and to be incomplete. Expect all APIs to change. See README: https://github.com/lenalebt/timeular-cli/blob/0.1/README.md

I expect future releases to also have a package for Mac OS X.