cleanup interfaces.widget.php
Fix an attempt to read unset variable $rtent
Merge pull request #822 from CharlieMarshall/interfacesWidget

cleanup interfaces.widget.php
Make return_gateways_array() return all disabled gateways when $disabled is true, it should fix #3291
fix typo
Define dynamic gateway for GRE interfaces and do not user to define IP address to the interface. Fixes #3280
Revert "Define dynamic gateway for GRE interfaces and do not user to define IP address to the interface. Fixes #3280"

Another solution will be implemented

This reverts commit 6721d6d0443bd7e697bd6ca33f470c801608df7e.
Add an Authentication Digest Algorithm drop-down to OpenVPN server/client (SHA1 is the default since that is OpenVPN's default)
Add Auth Digest to OpenVPN wizard also.
Change OpenVPN Compression settings to cover the full range of allowed settings on OpenVPN (unset, off, on, adaptive) rather than a simple off/on switch that either doesn't set the value or enables it with adaptive (OpenVPN's default).
Unset value should be '' and not  'none'