Command - prepend

- Migrated handlePrepend to CmdPrepend.

src/Cmd.cpp

@@ -153,7 +153,6 @@ void Cmd::load ()
     commands.push_back ("duplicate");
     commands.push_back ("import");
     commands.push_back ("log");
-    commands.push_back ("prepend");
     commands.push_back ("start");
     commands.push_back ("stop");
     commands.push_back ("summary");
@@ -256,7 +255,6 @@ bool Cmd::isWriteCommand ()
       command == "duplicate" ||
       command == "import"    ||
       command == "log"       ||
-      command == "prepend"   ||
       command == "pull"      ||
       command == "start"     ||
       command == "stop"      ||