Add clang-format configuration.

For now, it uses tabs like before, to make the diff easier to read/check.
One of following commits will switch it to spaces.

modules/missingmotd.cpp

@@ -17,7 +17,7 @@
 #include <znc/Modules.h>
 
 class CMissingMotd : public CModule {
-public:
+  public:
 	MODCONSTRUCTOR(CMissingMotd) {}
 
 	void OnClientLogin() override {
@@ -25,11 +25,10 @@ public:
 	}
 };
 
-template<> void TModInfo<CMissingMotd>(CModInfo& Info)
-{
-    Info.SetWikiPage("missingmotd");
-    Info.SetHasArgs(false);
+template <>
+void TModInfo<CMissingMotd>(CModInfo& Info) {
+	Info.SetWikiPage("missingmotd");
+	Info.SetHasArgs(false);
 }
 
 USERMODULEDEFS(CMissingMotd, "Sends 422 to clients when they login")
-