Edited the test_dataqc_solarelevation function to fix np.timedelta error
added sflpres_l1
added sflpres_l1 test
edited code to address comments
edited solarelevation to address py version issue
Merge pull request #112 from crisien/qaqc

CIDEVMI-1085 Fix error in solar elevation.
Merge pull request #110 from crisien/sfl

Title: CIDEVMI-1055 Added PRESF Class