modeling.pek1d - added new module

Added module to deal with inputs and outputs from pek and santos (2006)
1d anisotropic inversion code
pek1d - various updates/additions
pek1d - added if workdir doesn't exist, create it
pek1d - rewrote plot function + small changes

changed import of mtpy.core.edi from e to mtedi
changed __init__ to include calculation of lat and lon - need to change
this to more robust solution but this will do for now
rewrote plot model function. now it can plot inmodel as well for
comparison.
utils.exceptions: added module import exception
pek1d

remove setting absolute error for diagonals
pek1d

add back absolute errorfloor setting. plus a few other changes
pek1d - change interpolator

si.interp2d not working properly for latitude and longitude, change to
linearndinterpolator
Complete restructure of pek1d

created classes for each input/output file and these are read in by
pek1d which does the model setup. also added a pek1dplotting module
which was previously contained in pek1d. Miscellaneous functions have
been merged to utils.
Bug fixing of Pek1d
Starting some new modules
Adding modules to run multiple models using MPI
update
Updating modules to run suite using MPI4py
pek1d - more updates to MPI module
pek1d - change so script doesn't read argv[0]
filehandling-unique folder - fix so there is default basename
pek1d - bug fixes
pek1d,filehandling making savepath

change so it checks whether path exists
pek1d - updates to savepath conventions