Emacs: Change default Linux font to Droid Sans Mono

Signed-off-by: Ratheesh S <ratheeshreddy@gmail.com>
Tested-by: Ratheesh S <ratheeshreddy@gmail.com>
Tmux: Rearrange status bar details

Currently Timezone information was displayed in the status bar. This is
redundant since I do not travel very often and adding to this, time
itself reflects the timezone if changed. Hence remove this to make some
space for windows.

Additional changes:
* Make changes to date display.
* Display time with seconds
* Change some colors to status bar elements

Signed-off-by: Ratheesh S <ratheeshreddy@gmail.com>
Tested-by: Ratheesh S <ratheeshreddy@gmail.com>