Allow modification of the component of the specified tuple.

[CMake] Moved packaging executable dependencies to package target.

BoundaryConditionBuilder

Beforehand this logic was executed in a forced addional CMake run
everytime after the specific executable was built. Now this is done
at the moment this information is needed (at building the package or
install target).

Same as in previous Neumann test from 1e-15 to 1e-14.

Material model for fracture deformation

Use mesh subsets instead of mesh nodes

... for the given variable and component ids instead of all element nodes,
which might not be a part of the associated mesh subset.

Enable travis' trusty ci-environment.

Mainly for upgrading clang from version 3.4 which cannot compile certain
code, which is fine on newer version or MSVC or gcc.

Relax tests tolerances

In the last time step the absolute maximum norm error is 1.24e-14 on
jenkins' large test run.

Because the tests fail for large (in norm) vectors, the slope is increased.

Finished unit tests for time integration

Move dof table functionality