Fix even more E684 errors and improve class name guessing

Added explicit guard against the condition when previous context cannot
be determined. Also made the forward parsing for previous contexts way
more robust against whitespaces (including newlines), comments and strings.

Previously this context's end was simply the line where the variable in
search was defined, now it searches the file for the next non comment or
string ';'
Remove dist version of the plugin

This thing proven to be useless and hard to track.