#1244 Transparent versions of the logo graphics and icons.
#1245 Icons and graphics for use on a dark background.
updated comment regarding the missing 32x32 and 48x48 sizes for the dark background graphics.
Updated API docs for TouchCollection.cs.
Merge pull request #1307 from totallyeviljake/ISSUE_1245_R1

Issue 1245 Graphics For A Dark Background
Merge pull request #1306 from totallyeviljake/ISSUE_1244_R1

#1244 Transparent versions of the logo graphics and icons.
Merge pull request #1313 from raistlinthewiz/touch-collection-api-docs

Updated API docs for TouchCollection.cs.