Changed crosshairs to only extend 1/3 of the radius of the circle as 
requested in #183.
Merge pull request #186 from drusk/smaller_crosshair

Smaller crosshair
Crosshairs on source marker now come from the outer part of the circle
pointing inwards but not intersecting.
Merge pull request #187 from drusk/outer_crosshair

Closes #183.
Merge branch 'master' into triplet_downloads