Remove implicit conversion operator from RString to const char*

This is required for the RString to std::string migration.

Mostly automated from https://github.com/aeubanks/rewriter/blob/main/c_str.cc, with some manual intervention required for fixing up `a + b.c_str()` to `(a + b).c_str()`.

Added some overloads for some common global functions like sm_crash to reduce the number of changes required here.

src/NoteSkinManager.cpp

@@ -215,7 +215,7 @@ bool NoteSkinManager::NoteSkinNameInList(const RString name, std::vector<RString
 {
 	for(size_t i= 0; i < name_list.size(); ++i)
 	{
-		if(0 == strcasecmp(name, name_list[i]))
+		if(0 == strcasecmp(name.c_str(), name_list[i].c_str()))
 		{
 			return true;
 		}