fix Banword can be fooled with character case

[MysteriousDev 10]

Hello. I have a really easy fix for the default CBanwordManager::CheckString implementation. So the issue is: lets say we have a word "bitch" defined in banword. If we pass string "Bitch" through the CheckString it will return false which is not a proper behaviour. Players can remove insult.txt content from the client and name their characters with profane words avoiding the proper check. Lets get into it.
 

diff --git a/game/src/banword.cpp b/game/src/banword.cpp
--- a/game/src/banword.cpp
+++ b/game/src/banword.cpp
@@ -39,8 +39,11 @@
 	__typeof(m_hashmap_words.begin()) it = m_hashmap_words.begin();
 
+	std::string input(c_pszString, _len);
+	std::transform(input.begin(), input.end(), input.begin(), ::tolower);
+
 	while (it != m_hashmap_words.end())
 	{
 		const std::string & r = it->first;
-		const char * tmp = c_pszString;
+		const char * tmp = input.c_str();
 		ssize_t len = _len;