Dialog for loading a schematisation from 3Di working directory

[leendertvanwolfswinkel]

Similar to what we have implemented for loading 3Di results in 3Di Results Analysis: https://github.com/nens/ThreeDiToolbox/issues/721

• [x] The dialog should look like this: (Except that in the screenshot, in some cases there are multiple rows for one combination of schematisations/revision nr., which makes sense for results, but is not possible for schematisations)

• [x] The first tab of the dialog is populated with all the schematisations that are available in the 3Di Working Directory (as defined in the project settings by 3Di Models & Simulations). The list should include revisions in the revision {n} folders as well as those in the work in progress folders. Please show the revision number for the work in progress folder as {n} (work in progress).

• [x] The second tab should simply contain a QgsFileWidget to select a spatialite from any location the user browses to (i.e. the current implementation)

• [x] Double-clicking a row should also load the schematisation

• [x] If it is known which schematisation revision has been downloaded or created most recently, this one should be highlighted/selected.

[leendertvanwolfswinkel]

Please add your planning poker estimate with Zenhub @ldebek

[ldebek]

@leendertvanwolfswinkel Implementation ready for testing is now available on branch: https://github.com/nens/threedi-schematisation-editor/tree/enhancement_117

[leendertvanwolfswinkel]

@ldebek excellent, please merge