remove list output (dataframe is default now)
docstring cleanup in map()
many comment fixes
the rest of dataframe output (see the previous commit too)
basic serial map test with many fixes in map
dumpdb headers
dumpdb() operates on DataFrames now

inspired by 43fb580 (thanks to Jörg Encke)
loaddb() operates on DataFrames now

inspired by 43fb580 (thanks to Jörg Encke)
dumpdb test (still failing thou)
todo update
todo update
hardcore merge