Removed weaBus.sol for OpenModelica.

Removed the expandable connector sol from the expandable connector
weaBus as this construct does not work in OpenModelica.
Deleted the expandable connector SolarSubBus.
Renamed the following variables on the weather data bus:
sol.zen -> solZen
sol.dec -> solDec
sol.alt -> solAlt
Deleted SolarSubBus.mo
Merge branch 'master' into openmodelica-weather
Merge branch 'openmodelica' into openmodelica-weather
Updated release notes and conversion script.

This is for the update of the weather data bus.
Merge pull request #301 from lbl-srg/openmodelica-weather

Openmodelica weather bus compatibility