tabasco did not return (invisibly) correct indices when dendrograms were used

git-svn-id: svn+ssh://svn.r-forge.r-project.org/svnroot/vegan/pkg/vegan@2435 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
put tabasco origin to the upper left corner instead of lowerleft

git-svn-id: svn+ssh://svn.r-forge.r-project.org/svnroot/vegan/pkg/vegan@2436 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
tabasco & vegemite know cluster::agnes trees, and tabasco can handle picante::phylo trees for species (not tested)

git-svn-id: svn+ssh://svn.r-forge.r-project.org/svnroot/vegan/pkg/vegan@2437 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
we need to require() packages for method functions, and we don't want to add picante to vegan dependencies

git-svn-id: svn+ssh://svn.r-forge.r-project.org/svnroot/vegan/pkg/vegan@2438 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Merge branch 'r-forge-svn-local'