IniFile: Added common code to migrate ports.

Old settings have IPv4 and IPv6 ports as separate values, new settings have a single value for the ports.

src/IniFile.h

@@ -15,9 +15,7 @@
 !! MODIFIED BY FAKETRUTH and madmaxoft!!
 */
 
-#ifndef CIniFile_H
-#define CIniFile_H
-
+#pragma once
 
 
 
@@ -215,4 +213,22 @@ public:
 
 // tolua_end
 
-#endif
+
+
+
+
+/** Reads the list of ports from the INI file, possibly upgrading from IPv4/IPv6-specific values into new version-agnostic value.
+Reads the list of ports from a_PortsValueName. If that value doesn't exist or is empty, the list is combined from values
+in a_OldIPv4ValueName and a_OldIPv6ValueName; in this case the old values are removed from the INI file.
+If there is none of the three values or they are all empty, the default is used and stored in the Ports value. */
+AStringVector ReadUpgradeIniPorts(
+	cIniFile & a_IniFile,
+	const AString & a_KeyName,
+	const AString & a_PortsValueName,
+	const AString & a_OldIPv4ValueName,
+	const AString & a_OldIPv6ValueName,
+	const AString & a_DefaultValue
+);
+
+
+