add features & fixes to OsRaster and CI/CD

See merge request !1

- update to graphab 2.8
- default nodata to 255

 Conflicts:
	processing/CreateProject.py

- add Graphab version parameter in processing settings

- add Graphab version parameter in processing settings

- allow land cover creation without Java

Improvement of a feature that transform a raster file in a virtual raster file. The goal is to improve the speed of processes done on different rasters, but I don't see any difference and sometimes it's worst that's why the feature is kept in comments for the moment

Add of a README.md file. Add source of user guide for the plugin in english and french. Update the version number and remove the experimental flag.

Code simplification. Bug fix merge table edit when the tab was switch. Add of commentary. Add of french translation. Typo fix in one error message.

Bug fix reprojection for raster, if the resolution or the extent of the raster were different that the output value the raster wasn't reprojected to fit with the output.

Improvement of raster/vector filepath in qTableWidget. Code simplification. Bug fix for the extent (interface inputs were reversed, for example north/sud input were used for the x axe but have to be used for y axe). Improvement of extent verification, an error message tells you if the extent use give you an output with 0 pixels.

Improvement of qTableWidgets, now they take the maximum space possible and that space is use to show a maximum of raster/vector file paths.

Adaptation of the way to see a path of a raster/vector loaded on linux. French translation improvement. Vector dialog window improvement.

We can now see only the ending of a file from a raster/vector loaded before extending the header of the table. Bug fix import population tableWidget.

Bug fix output raster was of type Float32 but has to be UInt16. Add of verifications for nodata and encoding value that have to be between 0 and 65 535. Bug fix division by 0 with the resolution. Improvement of french translation. Warning fix about regex from xmlToPython.py module.