Remove $ signs in quoted text

In order to prevent PowerShell from expanding non existing variables
in quoted text, the dollar sign was replaced with S.

Iw considered making single quoted text, but that interferred with
the back-apostrophe (`) which is alse present in the text.

Author: ReneNyffenegger

scripts/write-ascii-image.ps1

@@ -19,13 +19,13 @@ WriteLine ""
 WriteLine "              _-o#&&*''''?d:>b\_"
 WriteLine "          _o/'`''  '',, dMF9MMMMMHo_"
 WriteLine "       .o&#'        `'MbHMMMMMMMMMMMHo."
-WriteLine "     .o'' '         vodM*$&&HMMMMMMMMMM?."
-WriteLine "    ,'              $M&ood,~'`(&##MMMMMMH\"
+WriteLine "     .o'' '         vodM*S&&HMMMMMMMMMM?."
+WriteLine "    ,'              SM&ood,~'`(&##MMMMMMH\"
 WriteLine "   /               ,MMMMMMM#b?#bobMMMMHMMML"
-WriteLine "  &              ?MMMMMMMMMMMMMMMMM7MMM$R*Hk"
-WriteLine " ?$.            :MMMMMMMMMMMMMMMMMMM/HMMM|`*L"
+WriteLine "  &              ?MMMMMMMMMMMMMMMMM7MMMSR*Hk"
+WriteLine " ?S.            :MMMMMMMMMMMMMMMMMMM/HMMM|`*L"
 WriteLine "|               |MMMMMMMMMMMMMMMMMMMMbMH'   T,"
-WriteLine "$H#:            `*MMMMMMMMMMMMMMMMMMMMb#}'  `?"
+WriteLine "SH#:            `*MMMMMMMMMMMMMMMMMMMMb#}'  `?"
 WriteLine "]MMH#             ''*''''*#MMMMMMMMMMMMM'    -"
 WriteLine "MMMMMb_                   |MMMMMMMMMMMP'     :"
 WriteLine "HMMMMMMMHo                 `MMMMMMMMMT       ."