Display facts for aliases in *BSD

* interfaces.rb - aliases on *BSD are iterated over up to their actual count - slightly modified Michelle Sullivan's version
* util/ip.rb - added get_alias_no method to return alias count; method get_interface_value modified by Michelle Sullivan to allow obtaining values for specific aliases

Originated here:
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=190796

Linux, AIX, Solaris alias interfaces are seen as completely new interfaces, this will not affect any platform that sees an interface alias as a new interface.

eg:
Linux sees: ipaddress_eth0:0
Solaris sees: ipaddress_hme0.1 
etc..