fixed moveBackToLineStart() method on ZString.

ZString.cpp

@@ -586,8 +586,10 @@ namespace coreutils {
 
    void ZString::moveBackToLineStart() {
       while(cursor != data) {
-	 if(*cursor == '\n')
-	   break;
+	 if(*cursor == '\n') {
+	    cursor++;
+	    break;
+	 }
 	 cursor--;
       }  
       return;