Update doc formatting

* make PDF content copy&paste-able
* add new `\code{}` command

Signed-off-by: Steffen Jaeckel <s@jaeckel.eu>

Author: sjaeckel

doc/crypt.tex

@@ -1,4 +1,5 @@
 \documentclass[synpaper]{book}
+\usepackage[T1]{fontenc}
 \usepackage{geometry}
 \usepackage{hyperref}
 \usepackage{makeidx}
@@ -44,6 +45,7 @@
 \def\C{{\mathbb C}}
 \def\Q{{\mathbb Q}}
 \definecolor{DGray}{gray}{0.5}
+\newcommand{\code}[1]{\texttt{\textit{#1}}}
 \newcommand{\emailaddr}[1]{\mbox{$<${#1}$>$}}
 \def\twiddle{\raisebox{0.3ex}{\mbox{\tiny $\sim$}}}
 \def\gap{\vspace{0.5ex}}