Add the possibility of using wildcards when defining a proxy server when
creating a host with the command create_host

This functionality can be used to define a group of proxies from where
the system will choose a random proxy.

e.g:

If we have these three servers:

- proxy-prod01.example.net
- proxy-prod02.example.net
- proxy-test.example.net

proxy=proxy-prod01.example.net will use proxy-prod.example.net as the proxy to use while
proxy=proxy-prod* will random choose one of the two proxy-prod* servers as the proxy to use.
Merge branch 'master' of github.com-usit-gd:usit-gd/zabbix-cli