[test.elliptic-cg-discretization] use overloaded operator- instead of Difference
[tests.spaces] move tests for cg-spaces in a separate file
[tests.elliptic-discretizations] silence warnings and add HAVE_DUNE_FEM_LOCALFUNCTIONS-guard
[tests.elliptic-testcases.hh] silence warnings
Merge remote-tracking branch 'official/master' into fem-cmake-integration
Merge branch 'fem-cmake-integration' of https://github.com/pymor/dune-gdt into fem-cmake-integration
[spaces.discontinuouslagrange] add pdelab- and fem-based dg-space, remove fem-localfunctions-based dg-space
[spaces.interface] whitespace fix
[spaces.continuouslagrange] remove fem-localfunctions.hh
[tests] move dg-space tests to separate file
[playground.spaces] move femlocalfunctionsbased spaces to playground
[spaces.discontinuouslagrange.fem] add missing compute_pattern method
[spaces.discontinuouslagrange.pdelab] use discontinuous space
[tests.spaces_dg] add maps_correctly test
[tests.spaces] silence warnings
[spaces.discontinuouslagrange.pdelab] make PdelabBased pass tests
[tests.spaces_dg] fix P1Q1_Discontinuous_Lagrange test, clean up space definitions
[tests.spaces_dg] fix guards
[tests.spaces_dg] make maps_correctly() work with simplicial grids
[dune.gdt.operators and tests.elliptic-*discretization] replace FemlocalfunctionsBased spaces bei FemBased spaces