REF: A lot of formal changes in the dp module including renaming of functions and an enhancement of process_raw_phidp2.
REF: A lot of formal changes in the dp module including renaming of functions and an enhancement of process_raw_phidp2.

Providing more informative function names

kdp_from_phidp --> kdp_from_phidp_finitediff

kdp_from_phidp2 --> kdp_from_phidp_linregress

kdp_from_phidp3 --> kdp_from_phidp_sobel

kdp_from_phidp4 --> kdp_from_phidp_convolution

process_raw_phidp2 --> process_raw_phidp_vulpiani

process_raw_phidp_vulpiani now also does the iterative phdp kdp estimation. The
number of iterations is given by argument niter. The function now also returns
the kdp array that corresponds to phidp.

jjhelmus/wradlib,jjhelmus/wradlib