added PyHDF support and made plots consistent.
merge branch 'master' into issue82

Conflicts:
	zoo/nsidc/amsre/AMSR_E_L3_DL_A_TB36_5H_Res_1.py
	zoo/nsidc/modis/MYD29P1D_A2010133_h09v07_005_2010135182659_1km_Sea_Ice_by_Refl.py