doc/votl_readme.txt is just a copy of old votl.txt, remove it.

Fixes #53
Small corrections and updates
Updated TODO.otl
Add VimOutliner icons to the repository.
Modified to install.sh to:
1. Turn off backup functionality. (filename_time_date.old files)
2. Remove old backup clutter. (filename_time_date.old files)
3. Remove old vo_base.vim files from syntax, ftdetect and ftplugin
Removed unnecessary reserved mappings.