Improve error message for out-of-bound access in parallel vector
Merge pull request #275 from kronbichler/master

Improve error message for out-of-bound access in parallel vector
restructure and clean up some code
Code cleanup and several bugfixes

Refactor the creation of the final (possibly rotated) interpolation matrix
in make_periodicity_constraints into its own function. Add some additional
asserts to catch corner cases.

Return early if nothing to do (fixes dof_tools_21* tests)
Bugfix: Conditionally use matrix in orthogonal_equality

Only apply the parameter matrix in orthogonal_equality if it is a spacedim
x spacedim matrix and can be interpreted as a rotation.

Further bugfixes and documentation updates.
Use spacedim in compute_transformation instead of incorrect dim
make astyle happy