Remove CStr::ReverseFind

It was only used once. In this case a normal `std::string::find` can be
used.

source/ps/CStr.cpp

@@ -264,16 +264,6 @@ double CStr::ToDouble() const
 	return ret;
 }
 
-long CStr::ReverseFind(const CStr& str) const
-{
-	size_t pos = rfind(str, length() );
-
-	if (pos != npos)
-		return static_cast<long>(pos);
-
-	return -1;
-}
-
 // Lowercase and uppercase
 CStr CStr::LowerCase() const
 {

source/ps/CStr.h

@@ -131,16 +131,6 @@ public:
 	 **/
 	double ToDouble() const;
 
-	/**
-	 * Search the CStr for another string.
-	 * The search is case-sensitive.
-	 *
-	 * @param const CStr & str reference to the search string
-	 * @return long offset into the CStr of the last occurrence of the search string
-	 *				-1 if the search string is not found
-	 **/
-	long ReverseFind(const CStr& str) const;
-
 	/**
 	 * Make a copy of the CStr in lower-case.
 	 *