adding undo/redo
tree81544a49c10edfc2670c2c2b1b415faf19893318
-rw-r--r-- 92 .cvsignore
-rw-r--r-- 236 .gitignore
-rw-r--r-- 385 .hgignore
drwxr-xr-x - manual
drwxr-xr-x - src