Standardize properties on LoadSINQ,LoadSINQFile & LoadFlexiNexus.

Changes to the output workspace properties to work in the more
standard way that Mantid works with them.
Refs #7505
Rename C++ LoadSINQ to LoadSINQFocus as it only loads FOCUS data.

Deprecated in favour of new LoadSINQ
Refs #7505
Rename Nexus dictionaries to remove mantid prefix.

Now that they are within mantid the prefix seems redundant.
Refs #7505
Replace error logging with information level logging.

Refs #7505