Update issue #252 : 
Shift arrow to extend filter selection 
Control arrow to navigate pins
Control+Shift arrow to extend pin selection
Can only extend selection reliably to two. To work better we need to maintain and display a 'current' pin/filter for navigation in a different colour


git-svn-id: http://graph-studio-next.googlecode.com/svn/trunk@412 c2f33eb2-41b2-391d-4cb4-d9d0608729ba
Fix issue #254 : Escape key now clears filter or pin selection (in addition to stopping playback)

git-svn-id: http://graph-studio-next.googlecode.com/svn/trunk@413 c2f33eb2-41b2-391d-4cb4-d9d0608729ba