update plugintreeviewmodel
Merge branch 'master' into task_benedikt
start implementing a new function in SystemDbManager to query all available plugins
continue implementing plugin manager #8
start implementing default function configuration #8
Merge branch 'task_Jens' into task_benedikt
- BugFix: A feature should not get an empty name (when editing in table view)
- continue implementing default function
added QMaps with attributes to be displayed and functions that generate and select the attributes.
fixed bug in scalar entity dialog.
#6
Merge branch 'task_benedikt' into task_Jens
settings dialog has a new tab for managing the displayed attributes.
the gui elements are created dynamically. If there is a new attribute, you only need to specify it in the configuration class lists.
Proxymodel decides what column to display, by using the configuration class´ lists and functions.

#6