keep some configurations commented

Keep options I'm not yet able to appreciate commented out.
They might become meaningful enough to uncomment in the future.
git: add note for [include]

* [include] only works for git >1.7.10
* alternatively use ~/.secrets to define GIT_AUTHOR_NAME and
GIT_AUTHOR_EMAIL
tmux.conf: comment OSX-only tmux wrapper

* in OSX we wrap tmux with reattach-to-user-namespace to bring back
clipboard functionalities. Comment out for Linux
* remove few trailing spaces
vundels: add plugin for robotframework

* Vim plugins for development with Robot framework
* https://github.com/mfukar/robotframework-vim
tmux: add binding to send C-a to the terminal

* usefull with nested sessions
zsh: aliases: comment out some otherwise clashing

* some ruby related aliases would clash with cvs related: comment
them out for now
* also comment some ls/ll with options specific for OSX
move local pugins to .vundles.local
prezto ssh module throws errors: disable for now
I'm a bit confused... :-()