patterns_content without rowid
[learn] Fixing a bug where learn was causing -1 to be updated as word id

This happens when the same word gets learned multiple times. A bug which
happened because of caching the last learned word id. Last learned word
id was incorrectly set even if the word under learn is not a new word
Added Kevin to Authors list
change in scheme
Adding jaydeep to authors
Fixing lintian warnings