Simplify GenericDofMap::dofs() with sub-maps now storing ownership range.
Fix build problem
Merged master into blechta/add-mesh-quality-demo
Change an assertion to a proper error check fixing issue #166 as reported by Jan Blechta
Merged in blechta/add-mesh-quality-demo (pull request #70)

Fix build error in mesh quality demo
Merge branch 'johanhake/fix-issue-166'
Merge branch 'garth/simplify-dofmap-dofs'