refactor preamble into input file

inputs/preamble.tex

@@ -0,0 +1,13 @@
+
+\begin{warning}
+    This is not an official script!
+    This document was written in preparation for the oral exam. It mostly follows the way \textsc{Prof. Franke} presented the material in his lecture rather closely.
+    There are probably errors.
+\end{warning}
+
+\noindent The \LaTeX template by \textsc{Maximilian Kessler} is published under the MIT-License and can be obtained from \url{https://github.com/kesslermaximilian/LatexPackages}. % TODO
+\newline
+
+\noindent $\mathfrak{k}$ is {\color{red} always} an algebraically closed field and $\mathfrak{k}^n$ is equipped with the Zariski-topology.
+Fields which are not assumed to be algebraically closed have been renamed (usually to $\mathfrak{l}$).
+