Modified:
Corrected EPU polarization enum names
ADDED:
Added check for valid input source before calling
```computeCachedValues()``` in
```REIXSXESImageInterpolationAB::setCurve2Disabled()```
MODIFIED:
```REIXSXESImageInterpolationABEditor::onAnalysisBlockInputDataSourcesChanged()```
to properly sync second curve disabled settings
Merge pull request #1103 from acquaman/Issue1098

Pull Request for Issue1098 - REIXS crash on load XES scans