New Git alias: grr, like gr but much smaller--ignores linear parts

dotfiles/git-universe/before.gitconfig

   dc = !clear && git diff --cached
   gr = log --graph --full-history --all --color\
        --pretty=tformat:"%x1b[31m%h%x09%x1b[32m%d%x1b[0m%x20%s%x1b[0m"
+  grr = log --graph --full-history --all --color\
+        --pretty=tformat:"%x1b[31m%h%x09%x1b[32m%d%x1b[0m%x20%s%x1b[0m"\
+        --simplify-by-decoration
   rb = rebase
   rbi = rebase --interactive
   rmv = remote --verbose