[Trisquel-users] RARv3 support

[alonivtsan]

Perhaps some simple instructions should be given to users who wish to open  
RAR files.

Here is what I did:
sudo apt-get install build-essential libgnustep-base-dev libz-dev libbz2-dev  
libssl-dev libicu-dev
cd XADMaster (go to where the XADMaster folder is)
make -f Makefile.linux
./unar filename.rar