Added preliminary support for EAP-Key-Name

We use EAP-Session-Id internally, as not everyone wants to send
EAP-Key-Name in a packet.  The eaptls_gen_eap_key() function
generates the EAP-Session-Id.  The eaptls_success() function
calls the "gen key" function on success.  This means that
the key is available on all TLS-based EAP methods

If someone wants to send EAP-Key-Name, they should use unlang
to make EAP-Session-Id to EAP-Key-Name
Update the example to show EAP-Key-Name
Merge pull request #191 from candlerb/candlerb/redis_fixes_v2.x.x

Bug fixes for rlm_redis v2.x.x
Factor out argv splitting into rad_expand_xlat
Remove quotes from quoted argv entries
rlm_redis argument splitting

rlm_redis_query now splits the query into separate arguments and expands
each one individually.

This allows for both string literals and expansions to contain spaces, e.g.

    %{redis:LPUSH 'my key' %{User-Name}}
Remove superfluous redis_escape_func