added wcs_from_points function
added wcs_from_points function

saimn/astropy,MSeifert04/astropy,stargaser/astropy,MSeifert04/astropy,StuartLittlefair/astropy,larrybradley/astropy,stargaser/astropy,saimn/astropy,saimn/astropy,astropy/astropy,larrybradley/astropy,aleksandr-bakanov/astropy,larrybradley/astropy,stargaser/astropy,aleksandr-bakanov/astropy,larrybradley/astropy,StuartLittlefair/astropy,pllim/astropy,astropy/astropy,dhomeier/astropy,lpsinger/astropy,aleksandr-bakanov/astropy,aleksandr-bakanov/astropy,saimn/astropy,mhvk/astropy,MSeifert04/astropy,dhomeier/astropy,mhvk/astropy,pllim/astropy,dhomeier/astropy,lpsinger/astropy,StuartLittlefair/astropy,MSeifert04/astropy,stargaser/astropy,pllim/astropy,astropy/astropy,mhvk/astropy,StuartLittlefair/astropy,lpsinger/astropy,mhvk/astropy,saimn/astropy,StuartLittlefair/astropy,larrybradley/astropy,astropy/astropy,dhomeier/astropy,dhomeier/astropy,mhvk/astropy,lpsinger/astropy,pllim/astropy,lpsinger/astropy,pllim/astropy,astropy/astropy