Fixed DMG link
ModelVerification fix and dmg url fix
needed one more NP()
Added ability to weight the opacity of points by data and ability to set derivatives manually in time series
more ModelVerification corrections
xsd / schema fixes

- avoid double-schema loading (enforced by new version of lxml; thanks
lxml)
- fix XSD for PlotCanvas/DerivedField siblings
fix XSD for PlotCanvas/DerivedField siblings
dmg links
Alternate and baseline were reversed
Added ability to weight the opacity of points by data minor corrections
version upgrade

Moving to 0.6.beta3