SciDAVis - Improvements SVN-temp

Fixed bug #2099820 (Missing color indicators in PDF export)

Fixed constant fit parameters (naive string substitution fails if a parameter
name is a substring of something else, e.g. another parameter name).

This is a rather large patch for a bug-fix release, but there doesn't seem to
be an easy fix. Unfortunately, fast muParser-provided numerical differentiation
doesn't work with this ansatz, so non-linear fitting with user-defined
functions gets noticably slower.

- Fixed bug #1983861 (comments not shown after opening)
- Fixed some problems with exporting legends at high resolutions. Hard-coded
line width of border is still an issue, though.
- Fixed inward tick marks.
- Fixed graph layer cloning (auto-scaling fonts property wasn't copied).

- fixed a bug in AxesDialog that cause text based axes
to be set to numeric (this is probably related
to the second part in bug #2231471)

- fixed a bug that lead to all curves being removed when
any table column was removed

- ported the hack that prevents axes gaps in graph vector exports
(eps, pdf, svg) from QtiPlot
(closes bug #1984423)

- fixed another SIP related problem

- fixed another SIP related problem

- fixed incompatibilites with SIP >= v4.7.8

- fixed incompatibilites with SIP >= v4.7.8