Merge pull request #32 from Alewx/Development

regular update
minor fix in techRequired dropdown

A small precaution for the case, when techID can't be found in game's
DataBase.
The length of the list of titles always must match the length of the
list of techID's.
Added option to clear the editor or not

I propose to test the necessity of cleaning the editor
We need unlock editor even if hasn't cleared editor
Welder class fix

Now change of Welder.Category should not change techRequired
RE-FIX for "minor fix in techRequired dropdown "

re-fix for 70760b460545c1246fa49b310b4bae6109a617da
Now contentList.Add call has found it's right place
minor GUI improvments
Merge pull request #36 from girka2k/dev-test

Dev test
Merge pull request #6 from girka2k/dev

regular update