renamed layers 'experimental' area to 'commons'

added repository README file

finished organisms->layers content migration

documented migration of aster gdem1 and gtopo materials

folded Nunokawa backup file changes into vrt script file

cleaned up file permissions

added in various previously uncommitted scripts

added organisms->layers content migration 'script'

reorganized terrain-related files

removed obsolete/preliminary DEM 60N assessment scripts

removed obsolete/preliminary DEM 60N mosaicing scripts

removed obsolete/preliminary DEM regional mosaicing scripts

added old R script to assess our SRTM holdings

tweaked aster-check script to work from anywhere

added R script to compare ASTER tile names to locations

added PDF of boundary assessment doc sent to the group

final minor edits before posting to the group

just minor tweaks to code comments

added histogram plot of ASTER-SRTM differences

removed placeholder cruft from flowdir correlation plots

spell-checked boundary analysis doc (aspell)

more boundary analysis updates, especially discussion of stats

added correlations/RMSE discussion, plus many new edits

numerous changes and revisions to boundary assessment doc

switched plot to bin by SRTM elev rather than ASTER