[cpp.include] Fix odd parenthetical sentence.

Author: Stefanus Du Toit

source/preprocessor.tex

@@ -434,9 +434,9 @@
 (that does not match one of the two previous forms) is permitted.
 The preprocessing tokens after
 \tcode{include}
-in the directive are processed just as in normal text
-(Each identifier currently defined as a macro name is replaced by its
-replacement list of preprocessing tokens.).
+in the directive are processed just as in normal text, 
+(i.e., each identifier currently defined as a macro name is replaced by its
+replacement list of preprocessing tokens).
 If the directive resulting after all replacements does not match
 one of the two previous forms, the behavior is
 undefined.\footnote{Note that adjacent string literals are not concatenated into