Update submodule common
Add ToDo list for m2 (backend)
Merge branch 'master' into backend
Downgrade submodule to prevent breaking of tests

See https://github.com/swp-uebersetzerbau-ss13/common/issues/28
Add boolean arithmetic, comparisons, labels and branches

Pairprogrammed by Moritz Maxeiner and Jens Fischer.
Add boolean arithmetic, comparisons, labels and branches

Pairprogrammed by Moritz Maxeiner and Jens Fischer.
Merge branch 'experimental_backend' of github.com:swp-uebersetzerbau-ss13/fuc into backend

Conflicts:
	code/backend/src/swp_compiler_ss13/fuc/backend/LLVMBackend.java
Add print statements

All tests are set to @Ignore, they need to be refactored to work with the new
module header.
Fix tests to work with new module header
Add transformation of strings to being wellformed for LLVM IR, stdout+stderr printing to TACExecutor, and some minor bugfixes
Unify commenting
Add exit code as return value to runTAC()
Fix format string for printing longs
Merge branch 'experimental_backend' of github.com:swp-uebersetzerbau-ss13/fuc into backend

Conflicts:
	code/backend/src/swp_compiler_ss13/fuc/backend/TACExecutor.java
Fixes tests
Add runIR method, error handling and ExecutionResult TACExecutor
Add some runtime tests
Refactor TACExecutor for better access from tests

Separate the the execution from the LLVM IR code from the rest, so that runIR()
can be cleanly accessed from tests.
Add logging instead of console printing for TACExecutor
Add M1 integration tests

The integeration tests (M1ErrorTest and M1RuntimeTest) test the example
programmes against the hole compiler chain.
The RuntimeTest need a LLVM installation to work, because they execute the
LLVM IR code and check for the exitCode.
In particular the lli tool is needed. The RuntimeTest checks for a working LLVM
installation, if no installation is found the tests are ignored.