How to show time in Ubuntu 13.10 [duplicate]

Just upgraded from 13.04 to 13.10.

Everything went fine but I don't see the time in the top right corner of the 'top bar' anymore. I tried to right click on it so I could get some options but nothings shows.

I'm sure it's obvious but I don't see it.

Already solved here and here.
From the terminal:

sudo apt-get install indicator-datetime
sudo dpkg-reconfigure --frontend noninteractive tzdata
sudo killall unity-panel-service

Then logout & login from the graphic session.
If the clock is still hidden/grayed out:

If it still doesn't work report a bug on Launchpad.
*edited to solve a bigger slice of problems.

Go to Time & Date under System Settings, and after you click on it, click on the Clock tab, and make sure that there is a check mark in Show a clock in the menu bar. See image below.

Edit on behalf of @user221931 If the whole panel is grayed out, try (as mentioned already in another answer) the following commands in a terminal:

sudo dpkg-reconfigure --frontend noninteractive tzdata && sudo killall unity-panel-service