Fix maybe

src/erlmarkdown.erl

@@ -567,12 +567,12 @@ is_block_tag(_Other)       -> false.
 type_underscore(List) ->
     case type_underscore1(trim_right(List)) of
         hr    -> {hr, List};
-        maybe -> {type_underscore2(List), List}
+        'maybe' -> {type_underscore2(List), List}
     end.
 
 type_underscore1([])                          -> hr;
 type_underscore1([{{md, underscore}, _} | T]) -> type_underscore1(T);
-type_underscore1(_List)                       -> maybe.
+type_underscore1(_List)                       -> 'maybe'.
 
 type_underscore2(List) ->
     case trim_right(List) of % be permissive of trailing spaces
@@ -586,7 +586,7 @@ type_star(List) ->
     Trim = trim_right(List),
     case type_star1(Trim) of % be permssive of trailing spaces
         hr    -> {hr, trim_right(Trim)};
-        maybe -> Type = type_star2(List),
+        'maybe' -> Type = type_star2(List),
                  % if it is a normal line we prepend it with a special
                  % non-space filling white space character
                  case Type of
@@ -597,7 +597,7 @@ type_star(List) ->
 
 type_star1([])                    -> hr;
 type_star1([{{md, star}, _} | T]) -> type_star1(T);
-type_star1(_List)                 -> maybe.
+type_star1(_List)                 -> 'maybe'.
 
 type_star2(List) ->
     case trim_right(List) of