SciDAVis - Improvements SVN-temp

Better parsing of DataSets.

More code cleanup/readability improvements (from patch #2990795)

Add some lines missing in r1346.

Some code cleanup/readability improvements (from patch #2990795)

Improve some debug output (parts of patch #2990795)

Re-activate builtin Origin OPJ import using liborigin2.

This is mostly a patch by Miquel Garriga, with some additions and corrections.

Remove Python code for OPJ import importOPJ from current_stable.

It's not yet clear whether this or a liborigin based C++ version should be
included in one of the next releases, so remove for now and merge (selected)
results from origin_import branch later.

Create branch for development of OPJ file import filter(s).

Disallow \n, \r, \t in Aspect names.

While it's a bit non-trivial to enter these in the first place, succeeding in
doing so will easily result in broken project files - you just have to add a
column with such a name into a graph.

Closes bug #3003662.

Improved some links to online resources.

* Removed link to translations, which haven't been released independently since
SciDAVis 0.1.3.

* Made links to manual and updates more specific, closing bug #3019928.