Add a possibility to flexibly ignore custom Doxygen tags.

Add %feature("doxygen:ignore:<command>") implementation, documentation and
test case.

This feature allows to use custom tags in C++ Doxygen comments for
C++-specific things that don't make sense in the context of the target
language and also allows to insert contents specific to the target language in
the C++ comments using (different) custom commands, which is very useful in
practice to explain the particularities of the API wrappers.

Source/DoxygenTranslator/src/DoxygenParser.h

@@ -39,6 +39,7 @@ private:
     COMMANDUNIQUE,
     COMMAND_HTML,
     COMMAND_HTML_ENTITY,
+    COMMAND_IGNORE,
     END_LINE,
     PARAGRAPH_END,
     PLAINSTRING,
@@ -98,6 +99,17 @@ private:
   std::string m_fileName;
   int m_fileLineNo;
 
+  /*
+   * Return the end command for a command appearing in "ignore" feature or empty
+   * string if this is a simple command and not a block one.
+   */
+  std::string getIgnoreFeatureEndCommand(const std::string& theCommand) const;
+
+  /*
+   * Helper for getting the value of doxygen:ignore feature or its argument.
+   */
+  String* getIgnoreFeature(const std::string& theCommand, const char* argument = NULL) const;
+
     /*
      * Whether to print lots of debug info during parsing
      */
@@ -334,6 +346,14 @@ private:
                        const TokenList &tokList,
                        DoxygenEntityList &doxyList);
 
+  /*
+   * Simply ignore the given command, possibly with the word following it or
+   * until the matching end command.
+   */
+  int ignoreCommand(const std::string& theCommand,
+                    const TokenList &tokList,
+                    DoxygenEntityList &doxyList);
+
   /* 
    * The actual "meat" of the doxygen parser. Calls the correct addCommand...()
    * function.