Implemented calculation for CO2FLUX with nose and performance tests
removed commenting from co2_performance tests
Merge branch 'master' into co2
Merge pull request #62 from s-pearce/spworking

METBK functions and clean-ups of vel_functions, generic_functions and readme.
Merge branch 'master' into co2
Merge pull request #63 from cwingard/co2

Adds CO2FLUX_L2 calculation
updated the test data set for the metbk functions to be the same as the DPS