Add ssad files for different spatial grains
Added community matrix at each of the spatial grains of interest
Update gen_comm_matrix() such that the matrix is numeric rather than string if the argument for the grain suffix is NULL
Add exportation of ssad at several different grains.
Merge remote-tracking branch 'upstream/master'
Merge pull request #14 from dmcglinn/master

Add SSAD files for several different spatial grains