Many sr-users seems to have the same problem with the documentation of uac module for requesting the actuall state of upstream sip-registrations.

### Description

kamcmd uac.reg_enable auth_username 12345678 Not working

kamcmd uac.reg_enable auth_username s:12345678 Working

### Expected behavior

Documentation should meantion the kamcmd s: prefix for converting - in the examples. Meanfull if you are using a mysql-db. Dont testet all backends that are possible.

https://lists.kamailio.org/pipermail/sr-users/2019-June/105993.html https://lists.kamailio.org/pipermail/sr-users/2017-August/098168.html

#### Actual observed behavior

#### Debugging Data

``` (paste your debugging data here) ```

#### Log Messages

<!-- Check the syslog file and if there are relevant log messages printed by Kamailio, add them next, or attach to issue, or provide a link to download them (e.g., to a pastebin site). -->

``` (paste your log messages here) ```

#### SIP Traffic

<!-- If the issue is exposed by processing specific SIP messages, grab them with ngrep or save in a pcap file, then add them next, or attach to issue, or provide a link to download them (e.g., to a pastebin site). -->

``` (paste your sip traffic here) ```

### Possible Solutions

<!-- If you found a solution or workaround for the issue, describe it. Ideally, provide a pull request with a improvement. -->

### Additional Information

* **Kamailio Version** - output of `kamailio -v`

``` kamailio -v version: kamailio 5.2.3 (x86_64/linux) c36229 flags: STATS: Off, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144 MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: c36229 compiled on 11:28:11 May 22 2019 with gcc 4.8. ```

* **Operating System**:

``` lsb_release -a LSB Version: :core-4.1-amd64:core-4.1-noarch Distributor ID: CentOS Description: CentOS Linux release 7.6.1810 (Core) Release: 7.6.1810 Codename: Core ```