[raster.reproject] several changes to function call and behaviour:
[raster.reproject] several changes to function call and behaviour:

- use spatial.gdalwarp instead of subprocess call
- added input parameter type checks
- new parameter targetres
- new default for parameter format: 'GTiff'
- new type options for parameters rasterobject and reference
- added documentation

johntruckenbrodt/pyroSAR,johntruckenbrodt/pyroSAR