[FEATURE]: Add sensor observation service plugin
Add sos selection dialog
Add soscapabilities class (not implemented yet)
Add/edit/remove connection in sos dialog
Request capabilities from QgsSOSCapabilities
Handle network and xml errors and get list of observable properties from capabilities
First sos client version that loads point features. Still needs a lot of debugging
Use hardcoded field structure for SOS response for now
Show progress dialog for sos source
Add sensor info maptool
Read data availability and display results in modeless dialog
Improvements to sensor info dialog
Show sensor data in a plot
Show time on x-axis
Added QgsXMLData as base class for streamed xml download
Subclass sosdata from xmldata
Show download progress in status bar
Port watermldata also to qgsxmldata, fix some bugs
Sort getData results by time
Handle dates before 1970, cleaner date -> int conversion