Updated comment in CMakeLists.txt
Updated comment in CMakeLists.txt

Added note explaining what CACHE STRING does in the set function

ds283/splinter,ds283/splinter,bgrimstad/splinter,ds283/splinter,bgrimstad/splinter,ds283/splinter,bgrimstad/splinter,lasote/multivariate-splines,bgrimstad/splinter,bgrimstad/splinter,ds283/splinter