Move versioning to a static library to improve trivial build speed (bug 5997 part 9, r=ds).

extensions/bintools/extension.cpp

@@ -61,11 +61,11 @@ bool BinTools::SDK_OnLoad(char *error, size_t maxlength, bool late)
 
 const char *BinTools::GetExtensionVerString()
 {
-	return SM_VERSION_STRING;
+	return SOURCEMOD_VERSION;
 }
 
 const char *BinTools::GetExtensionDateString()
 {
-	return SM_BUILD_TIMESTAMP;
+	return SOURCEMOD_BUILD_TIME;
 }