Unify angle type, with Isos for various units
WIP: Update for unified Angle type
add Hashable instance for SizeSpec2D
need ghc-prim package for GHC.Generics prior to 7.6
allow hashable-1.1
Merge remote-tracking branch 'origin/master' into unified-angle-type
Finish updating to use Angle type
Haddock fix: record update -> lens
allow array-0.5
added clipTo
added clipped and mdified clipTo not to set the trace
Another attempt at a proper intersection Trace in clipTo
Fix variable shadowing
return list of traces
SortedList
Add @@ operator for constructing Angles, using Iso
remove imports to compile with -Werror
Use @@ in place of 'review' or 'from'
Add Haddock docs for new Angle Isos
haddock: fix typo