Change target framework for WPF to .Net 4.5

We want to use Async/Await
Implement multithreading for Ciphers
Add Styled button
Fix HorizontalContentAlignment for RunningButton
Add CipherAnalysis and AutoSpaceControl
Change basic stylings
Remove async keyword
Merge pull request #13 from SquidDev/multithreaded-ciphers

Multithreaded ciphers (Fixes #12)