Removed print statements from doctests.
Removed print statements from doctests.

ManuSchmi88/landlab,csherwood-usgs/landlab,SiccarPoint/landlab,cmshobe/landlab,decvalts/landlab,cmshobe/landlab,RondaStrauch/landlab,landlab/landlab,amandersillinois/landlab,laijingtao/landlab,RondaStrauch/landlab,csherwood-usgs/landlab,cmshobe/landlab,Carralex/landlab,ManuSchmi88/landlab,ManuSchmi88/landlab,decvalts/landlab,landlab/landlab,Carralex/landlab,amandersillinois/landlab,Carralex/landlab,RondaStrauch/landlab,laijingtao/landlab,landlab/landlab,SiccarPoint/landlab