Fix whitespace in example of bad indentation: a comment indicated that one

line was not indented at all, so the example is no longer indented at all.
All of the errors being shown remain.

Typo: characteru --> character

Doc/ref/ref2.tex

@@ -196,7 +196,7 @@ The following example shows various indentation errors:
 
 \begin{verbatim}
  def perm(l):                       # error: first line indented
-    for i in range(len(l)):             # error: not indented
+for i in range(len(l)):             # error: not indented
     s = l[:i] + l[i+1:]
         p = perm(l[:i] + l[i+1:])   # error: unexpected indent
         for x in p:
@@ -327,7 +327,7 @@ String literals are described by the following lexical definitions:
   \production{shortstringchar}
              {<any ASCII character except "\e" or newline or the quote>}
   \production{longstringchar}
-             {<any ASCII characteru except "\e">}
+             {<any ASCII character except "\e">}
   \production{escapeseq}
              {"\e" <any ASCII character>}
 \end{productionlist}