Fixed picturebox not receiving focus when it was clicked on
Fixed problem when an area is being selected and the picturebox loses focus
Various small optimizations of the apply text effects code
Moved text to values code into a separate class

Added levels adjustment values to the batch conversion settings
Removed unnecessary boolean from TextProcessingSettings
Changed conversion from Brightness/Contrast->Levels->Stretch to Brightness/Contrast->Stretch-

>Levels to match what is shown on the graph
Made Brightness/Contrast widget resizable

Text image levels control
Improved Brightness/Contrast control event handling