RADIUS: Added support for session-timeout attribute.
RADIUS: Added support for session-timeout attribute.
Merge branch 'radius-timeout' of https://github.com/Oooska/pgina into radius-timeout

Conflicts:
	Plugins/Contrib/RADIUS/PluginImpl.cs
Updated Configuration UI and Settings options to support new features.

Replaced getIpAddress() method in PluginImpl.cs, method now returns the mac address and ip address
Added support for customizable called-station-id, nas-identifier. Added session-timeout support. RADIUS plugin returns the error message reported by the server to pGina.
Abstracted attribute-value pairs (AVP) from Packet, making it a subclass. Multiple attribute types of the same kind are now properly supported.
-Corrected config ui loadding incorrect values
-Updated RADIUSClient to give access to AVPs as byte arrays
-Added add'l debug info for vendor-specific attributes
-Force interim updates now works at the correct speed, instead of 1000x
faster.
-Added session.active attribute to indicate when an account has logged out
to stop rogue interim updates.
- Implemented account-sssion-time in Packet.cs

- Correctly specifies NAS-Identifier/NAS-IP-Address values during
  interim-update in Packet.cs.

- Added option to disablee accounting for non-RADIUS authed users in
  Settings.cs and Configuration.cs.

- Added static decode methods for devoding vendor-specified attributes in
  Packet.cs

- Incomplete wispr-Session-Terminate-Time support
- Added additional info to accounting packets.
- Corrected account-session-time value
-Added support for wispr-session-terminate-time
-Removed unnecessary debug info