Add tex for sidebars

Author: hadley

preamble.tex

@@ -23,3 +23,27 @@
 \newunicodechar{├}{\textfallback{├}}
 \newunicodechar{│}{\textfallback{│}}
 
+
+% sidebar environment
+\usepackage{framed,color}
+\definecolor{shadecolor}{RGB}{242,242,242}
+\makeatletter
+\newenvironment{sidebar}{%
+\medskip{}
+\setlength{\fboxsep}{.8em}
+ \def\at@end@of@kframe{}%
+ \ifinner\ifhmode%
+  \def\at@end@of@kframe{\end{minipage}}%
+  \begin{minipage}{\columnwidth}%
+ \fi\fi%
+ \def\FrameCommand##1{\hskip\@totalleftmargin \hskip-\fboxsep
+ \colorbox{shadecolor}{##1}\hskip-\fboxsep
+     % There is no \\@totalrightmargin, so:
+     \hskip-\linewidth \hskip-\@totalleftmargin \hskip\columnwidth}%
+ \MakeFramed {\advance\hsize-\width
+   \@totalleftmargin\z@ \linewidth\hsize
+   \@setminipage}}%
+ {\par\unskip\endMakeFramed%
+ \at@end@of@kframe}
+\makeatother
+