Proposed changes to hardcoded parameters during unwrapping

[bjmarfito]

• Changes are made to unwrap_fringe.py to incorporate parameters from xml files containing the wavelength, earthRadius and altitude values where the modifications where based from unwrap.py and s1a_isce_utils.py of topsStack
• Changes are made to integratePS.py and unwrapStack.py to write unwrapping scripts incorporating the xml file
• Changes in fringe/docs/workflow.md where the example code

unwrapStack.py -s slcs -m Sequential/miniStacks/ -d Sequential/Datum_connection/ -M 15 -u 'unwrap_fringe.py -m snaphu'

is changed to

unwrapStack.py -s slcs -m Sequential/miniStacks/ -d Sequential/Datum_connection/ -M 15 -u 'unwrap_fringe.py' --unw_method snaphu

to remove the existence of two different unwrapping methods on the run_unwrap.sh.

[bjmarfito]

Noted on this @hfattahi. Though, a structure same as with MintPy/GIAnT could probably help in making FRInGE a tool which could accept stacked SLCs from any InSAR processing software.