Sub Articulo 115.1

Someone already pointed out an answer for using \itemize in a tabular,
but your complaint about setting the width has me confused.  You have to
set the width for all p-type entries, and once you do that, your minipage
can use the same width.
I should mention that the solution works with the tabularx package
which makes variable-width p-type columns:
\usepackage{tabularx}
\makeatletter
\newcolumntype{I}{%
 >{\minipage[t]{\linewidth}\let\\\tabularnewline
    \itemize
       \addtolength{\rightskip}{0pt plus 50pt}% for raggedright
      \setlength{\itemsep}{-\parsep}}%
 X% <--- instead of "p{width}" 
 <{\@finalstrut\@arstrutbox\enditemize\endminipage}%
}
\makeatother
\begin{document}
..
\begin{tabularx}{\linewidth}{lXIr}
But if you have many very short items, you will still get a lot
of white space.  The way to put a series of narrow items in a single
tabular cell is with nested tabulars or a {tabbing} inside a minipage.
\begin{tabular}{ll}
Test & 
  \begin{tabular}{@{$\bullet$\enspace}l@{}}
   doe\\
   rae\\
   me\\
   fa\\
   so\\
   la\\
   tee
  \end{tabular}
\\
..
\end{tabular}
If you need enumeration, you have to declare your own counter (or use
one like "enumiii").
\setcounter{enumiii}{0}
\begin{tabular}{ll}
Test & 
  \begin{tabular}{@{\refstepcounter{enumiii}\theenumiii.\enspace}l@{}}
   doe\\
   rae\\
   me\\
   fa\\
   so\\
   la\\
   tee
  \end{tabular}
\\
..
\end{tabular}