Installation of MSP430's IDE Energia in Ubuntu
I don't believe it but I actually found a solution. Because, as I said in the question, I have searched extensively and most of the solutions were very messy and unclear I answer my question in the hope that it will help others and save them the hours I spent on this problem myself. This solution was hidden in a thread of a forum:

So in order to install Energia:


Download the binary release version from the energia site
Open the Ubuntu Software Center
Install the "Main Menu" package
From the first column select Accessories
Click New Item, name it Energia and select the file energia from the unzipped downloaded Energia binary release
Select Ok
Write Energia in Launcher and click on the Energia entry.


After that one must set up the serial communication with the Launchpad board. From another source I manage to find a solution to solve that problem doing the following:


sudo lsusb
sudo modinfo cdc-acm
Then create a file called 71-persistent-msp430.rules in /etc/udev/rules.d/ directory
Add this line in it:


ATTRS{idVendor}=="0451", ATTRS{idProduct}=="f432", MODE="0660", GROUP="plugdev"


sudo adduser user plugdev


Write your own username instead of user.


sudo service udev restart


Also it may need to change the Board from Energia's toolbar (Tools and after Board).