os-freeradius should allow colons in usernames and passwords

[meyergru]

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Is your feature request related to a problem? Please describe. When using RADIUS-based authentication for Mikrotik and Cisco switches, the MAC format is XX:XX:XX.XX:XX:XX. Standard on Cisco would be to user both username and password from the original MAC, but it is not possible to use that in os-freeradius plugin.

Describe the solution you'd like I would like to be able to use a colon in both username and password - Freeradius itself allows any UTF-8-character, so this should work right away.

Describe alternatives you've considered Even better would be to support any characters that Freeradius allows for.