added Fem namespace for dune-fem >= 1.4
[test.test_common] added Fem namespace for dune-fem >= 1.4
[localfunction.interface] added first draft, refs #230
[function.local] added wrapper around FunctionInterface
which fulfills the LocalFunctionInterface, not tested yet
moved function/local to localfunction/interface
[function.interface] added localFunction()
[function.interface] major changes
FunctionInterface -> GenericStationaryFunctionInterface
now FunctionInterface is only for nonparametric non timedependent
functions, refs #220
[function.expression] derived from new interface, refs #220
[function.affineparametric.coefficient] minor rename
[function.interface] minor update, refs #220
[function.checkerboard] derived from new interface
also redesign to allow for dimension dependent factory
methods, refs #220
[function.spe10model1] derived from new interface, refs #220
[test.function] update, refs #220
[function.affineparametric.coefficient] minor change
[function.interface] added ParametricFunctionInterface
and AffineParametricFunctionInterface, refs #220
[function.affineparametricinterface] added id()
[function.expression.base] minor fix
[function.affineparametric.checkerboard] updated to new interface
[test.function] added affineparametric test
[function.constant] added, refs #232