U_matrix fix
Tidying up

* Replace <<= with <<
* Reordering in put_Sigma
* Remove all instances of wien2triqs in doc
Change execs to setattr, getattr, etc
Moved out text file reading of Sigma from sumk_lda_tools
Converters clean up, new subgroup names

* Provided script update_archive.py to convert old h5 archives.
* Fixed all tests
Merge branch '1.2-dev' into transport

Conflicts:
	python/converters/wien2k_converter.py
	python/sumk_lda.py
	python/sumk_lda_tools.py