Submitted by: @fabianfrz, @DokuKaefer

Upgrade path is not for fiddling with the installed files,
we're importing config.xml, not a full base system.

Also adds a custom user agent to make it easier to filter by version
and moves the crash reporter to a more visible location in the system
category.  :)

(legacy) crashreport PHP Warning:  in_array() expects parameter 2 to be array, null given in /usr/local/www/services_dhcpv6_relay.php on line 162

(legacy) fix crashreport PHP Warning:  substr_count(): Empty substring in /usr/local/www/services_ntpd.php on line 290

Spotted by: @fabianfrz

Spotted by: @fabianfrz

Looks like fixes and additions, these will do good and
no harm.  :)

This page has been reworked on master so this is a tiny cherry-pick
to bridge the gap to 15.7.1x when we merge it in.