add offboresight angle + recalibration change

[vincelhx]

completed

[agrouaze]

Hello @vincelhx , can you do the basic tests to be sure all is OK with the changes proposed:

• [ ] open IW GRD for different IPF versions
• [x] generate the documentation make html ?

[vincelhx]

• [x] open IW GRD for different IPF versions
• [ ] generate the documentation make html -> not working