Looked for texi2dvi in Synaptics Package manager, but could not find it. I know it was present in Mint14-KDE.
I wanted to build the documentation for SBCL-1.1.9, but was unable to do so.
As a work-around, I copied the documentation from Mint14 to Mint15 and that got me going in that instance.
There will be other packages I'll need texi2dvi for that wont be so easy to work around.
Added after posting:
When I posted this, I didn't have access to my Mint14 system. Since then, I got back to my Mint14 system and discoovered that I should not have been searching for texi2dvi, but instead I should have been searching for texinfo. And then I also needed to install texlive and its associated packages. Then I could build the documentation for SBCL. Sorry for posting all of this unnecessarily. I should have waited until I had access to my Mint14 system.