Merge pull request #1418 from Cracert/i18n

[TRANSUP] pl: WebView, WMS
fix layer tree translation support
fix some warnings
sip: remove enum constants
[processing] all gdal algs now have the same icon

Did some code cleaning in gdal package
[processing] Use certain gdal algs in simplified mode instead of saga ones
[processing] helpfiles for scripts/models are now stored as json
[processing] first implementation of github-based resources manager
Add layer name to select by expression dialog title
Fix #10422
Updated IT GUI translation
North_Arrows

Additional arrows, including without Letter Marks and Surveying with
Declination
Add north arrow variants without text
Capitalization
[composer] Setting the composition for a composer view correctly creates item widgets and sets up connections for composer to composition (fix #10038)
[layertree] Add python bindings - part one (core)
[layertree] Add Python bindings - part two (gui)
VectorLayer, SymbolsList, WidgetShapeburst, XML, parent