patient -> subject
Implemented issue #56

Entries with missing values for grouping variable are removed for both tables on Distributions2 tab. Some files were renamed, some removed.
Some files removed/renamed.
Fixing errors when only one symptom selected #51

Managed to fix (hopefully) the first graph, but the second one is giving me grief. Data structures appear to be different when only one dimension exists and functions handle them differently (t(), apply()).
Added version info text output