remove sdl specific path modification
add process_or_read_hdf: use hdf store for pandas data frames
use process_or_read_hdf instead of process_or_unpickle
remove unused date conversion functions
add frame_apply_insert: modify frame by application of function; default to row-wise
add a script to demonstrate read, modification and write of a csv
demonstrate adding multiple columns
Merge branch 'master' of https://github.com/datakind/ctl
Merge branch 'sdl_analysis'