sync from my branch rev 983 and 993:

- module api change, if module fails to load it can give back an useful error message
- give a message when client doesnt supply a password when connecting
- some minor cleanup


git-svn-id: https://znc.svn.sourceforge.net/svnroot/znc/trunk@803 726aef4b-f618-498e-8847-2d620e286838

modules/email.cpp

@@ -93,7 +93,7 @@ public:
 			m_pManager->DelSockByAddr( vSocks[a] );
 	}
 
-	virtual bool OnLoad(const CString & sArgs) {
+	virtual bool OnLoad(const CString & sArgs, CString& sErrorMsg) {
 		m_sMailPath = sArgs;
 
 		StartParser();