make only one connection to every database
Merge pull request #31 from ssbunyk/master

make only one connection to every database
Added version property for mysql server
Added version column in UI
Merge remote-tracking branch 'upstream/master'
Modified unit tests for modeler according to modifications
PEP 8 modifications
Merge pull request #32 from ssirushchyshyn/master

Version property for MySQL server
reopen connection if any
Merge pull request #33 from ssbunyk/master

reopen connection in case it is stopped
Merge pull request #3 from ssvsergeyev/master

Fixes for issues