#582 R12 export & dimensions

[Antal Veres]

Version: 2.1.0-alpha
Commit: 2.1.0
Compiler: GNU GCC 4.8.4
Compiled on: Apr 25 2016
Qt Version: 5.2.1
Boost Version: 1.54.0
OS: ubuntu 14.04
Something wrong with the "save as" R12 format. After the saving when I reopen the drawing, all arrows of dimensions have an additional area pointing to 0;0 .