feat: group institute with author and subdue color

This change is mostly a result of the discussion at https://github.com/matze/mtheme/issues/180.

src/beamercolorthememoloch.dtx

@@ -113,7 +113,7 @@
 \setbeamercolor{titlelike}{use=normal text, parent=normal text}
 \setbeamercolor{author}{use=normal text, parent=normal text}
 \setbeamercolor{date}{use=normal text, parent=normal text}
-\setbeamercolor{institute}{use=normal text, parent=normal text}
+\setbeamercolor{institute}{use=normal text, fg=normal text.fg!80!normal text.bg}
 \setbeamercolor{structure}{use=normal text, fg=normal text.fg}
 %    \end{macrocode}
 %

src/beamerinnerthememoloch.dtx

@@ -114,8 +114,8 @@
     %
     %    \begin{macrocode}
     \ifx\beamer@shortauthor\@empty\else\usebeamertemplate*{author}\fi
-    \ifx\insertdate\@empty\else\usebeamertemplate*{date}\fi
     \ifx\insertinstitute\@empty\else\usebeamertemplate*{institute}\fi
+    \ifx\insertdate\@empty\else\usebeamertemplate*{date}\fi
     \vfill
     \vspace*{1mm}
   \end{minipage}
@@ -212,17 +212,6 @@
   \vspace*{2em}
   \insertauthor%
   \par%
-  \vspace*{0.25em}
-}
-%    \end{macrocode}
-% \end{macro}
-%
-% \begin{macro}{date}
-%   Set the date on the title page.
-%    \begin{macrocode}
-\setbeamertemplate{date}{
-  \insertdate%
-  \par%
 }
 %    \end{macrocode}
 % \end{macro}
@@ -231,7 +220,7 @@
 %   Set the institute on the title page.
 %    \begin{macrocode}
 \setbeamertemplate{institute}{
-  \vspace*{3mm}
+  \vspace*{0.5em}
   \insertinstitute%
   \par%
 }
@@ -239,6 +228,17 @@
 % \end{macro}
 %
 %
+% \begin{macro}{date}
+%   Set the date on the title page.
+%    \begin{macrocode}
+\setbeamertemplate{date}{
+  \vspace*{1.5em}
+  \insertdate%
+  \par%
+}
+%    \end{macrocode}
+% \end{macro}
+%
 %
 % \subsubsection{Section page}
 %