make colors user adjustable. (#151)

* make colors user adjustable.
- Systematize colors and make them user adjustable. See documentation for details.
  this requires the \moderncvcolor to be issued BEFORE \moderncvstyle.

* fix missing characters for fancy style

* manually copied the current version user guide form master

---------

Co-authored-by: David <forenkram@gmx.de>
Co-authored-by: LLdaniel <daniel.adlkofer2@freenet.de>
Co-authored-by: daniel <41345639+LLdaniel@users.noreply.github.com>

moderncvfooti.sty

@@ -79,7 +79,7 @@
     \fancyfoot[c]{%
       \parbox[b]{\footwidth}{%
         \centering%
-        \color{color2}\addressfont%
+        \color{addresscolor}\addressfont%
         \vspace{\baselineskip}% forces a white line to ensure space between main text and footer (as footer height can't be known in advance)
         \ifthenelse{\isundefined{\@addressstreet}}{}{\addtofoot[]{\addresssymbol\@addressstreet}%
           \ifthenelse{\equal{\@addresscity}{}}{}{\addtofoot[~--~]{\@addresscity}}% if \addresstreet is defined, \addresscity and \addresscountry will always be defined but could be empty
@@ -110,7 +110,7 @@
     \fancyfoot[c]{%
       \parbox[b]{\footwidth}{%
         \centering%
-        \addressfont\color{color2}%
+        \addressfont\color{addresscolor}%
         \vspace{\baselineskip}% forces a white line to ensure space between main text and footer (as footer height can't be known in advance)
         \vspace{-\baselineskip}% to cancel out the extra vertical space taken by the name (below) and ensure perfect alignment of letter and cv footers
         \strut{\bfseries\upshape\@firstname~\@lastname}\\% the \strut is required to ensure the line is exactly \baselineskip tall