Allow re-orientation of transistor schematic symbol

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Add a transistor symbol to a schematic
2. Right-click on the transistor symbol
3. No option to flip the symbol (e.g. change the emitter position to top / 
bottom of symbol)

Without this option it isn't possible to create some schematics in a logical 
and sensible layout.

Original issue reported on code.google.com by narrowbl...@googlemail.com on 15 Nov 2014 at 10:27