preamble cleanup

Remove unused package and custom colors

src/nix-at-ec/index.tex

@@ -90,8 +90,8 @@ \subsection{History}
             source some of its projects;
       \item Since 2019, the ECPHP team - the team I work in - has released a
             dozen of open source projects and materials used within European
-            Commission but also in other organisations. We are not the only team
-            doing that, there are other teams doing the same!
+            Commission but also in other organisations. We were one of the first
+            team doing that.
     \end{itemize}
   }
   \note<8>{

src/nix-at-ec/preamble.tex

@@ -5,42 +5,19 @@
 %\setbeamerfont{note page}{size=\tiny}
 %\setbeameroption{hide notes} % Only slides
 
-\usepackage{lipsum}
 \usepackage[utf8]{inputenc}
 \usepackage[T1]{fontenc}
-\usepackage{kantlipsum}
-\usepackage{listings,xcolor}
-\usepackage{spverbatim}
-\usepackage{amssymb}
-\usepackage{amsmath}
-\usepackage{array}
-\usepackage{textcomp}
-\usepackage{ragged2e}
 \usepackage{hyperref}
-\usepackage[normalem]{ulem}
-\usepackage{textcomp}
-\usepackage{caption}
-\usepackage{pgfpages}
 \usepackage{transparent}
 
-\definecolor{dkgreen}{rgb}{0,.5,0}
-\definecolor{dkblue}{rgb}{0,0,.6}
-\definecolor{dkyellow}{cmyk}{0,0,.8,.3}
-\definecolor{ecbluebackground}{RGB}{29,34,65}
-\definecolor{ecblue}{RGB}{54,167,223}
-\definecolor{ecgrey}{RGB}{77,77,77}
-\definecolor{ecpink}{RGB}{237,6,120}
-\definecolor{IcebergSky}{RGB}{150,220,254}
-\definecolor{IcebergDeepBlue}{RGB}{0,131,195}
-\definecolor{mainyellow}{RGB}{255,209,41}
-\definecolor{lightblue}{RGB}{34,117,176}
+\usetheme{ec}
 
 \input{version}
 \input{frames}
 
 \title{State of Nix}
 \subtitle{at European Commission}
-\institute{\href{mailto:[email protected]}{European Commission - Digit B4}}
+\institute{\href{mailto:[email protected]}{European Commission - DIGIT}}
 \date[2022]{October 2022}
 \author[Pol]{Pol Dellaiera}
 \logo{
@@ -50,10 +27,4 @@
   \includegraphics[trim=0 0 0 3mm,scale=0.25]{logo-ce-en}
 }
 
-\usetheme{ec}
-
-\newenvironment{itquote}
-{\begin{quote}\itshape}
-    {\end{quote}\ignorespacesafterend}
-
 \setbeamersize{text margin left=5mm,text margin right=5mm}