Feature/alter processing

related #54 (closed)

Implemented options of salome_script.py alter

• --times (need specific version of telemac)
• -f TFROM, --from TFROM specify the first frame included
• -s TEND, --stop TEND specify the last frame included (negative from the end)
• -d TSTEP, --step TSTEP specify the step for the extraction of frames
• --vars XVARS specify which variables should remain (','-delimited)
• --X+? ADD_X adds to the meshx
• --Y+? ADD_Y adds to the meshy

Graphical user interface

• add model for mesh dataset and times display
• update model for times display for time index range

Documentation

• first version of documentation

Tests

• creation of QGIS tests based on test_alter.sh

Limitation

⚠ Some functionalities couldn't be tested because telemac must be updated.

• times index selection not tested : need specific version of telemac