all templates should be placed into a separate .d directory and explicitely loaded before other contexts

[lelutin]

I've just discovered that contexts that use a template, e.g. [blah](sometemplatecontext) should be loaded after the template context itself, otherwise the whole configuration is invalid. asterisk was able to start with this type of configuration error but all of the sip peers were just not present anymore!

so to make configuration more robust, we should displace all contexts defined as a template (e.g. template_name == '!') into a separate directory and have all files in that directory be loaded before all of the non-template contexts.