MAESTRO-3772 Extensions to Tomcat plugin

1. Added support for the 'timeout' and 'max_connect_attempts' values that were already present
2. Added support for https (via 'tomcat_root_url' param below)
3. Added support for non-root tomcat location, if for example behind a proxy (via 'tomcat_root_url' param below)
4. Added a new param 'tomcat_root_url' that defaults to '/'.  See description below of function.

Existing params 'host' and 'port' are no longer required as they can be specified as part of 'tomcat_root_url'.
'tomcat_root_url' is used in two ways:

#1 - if only contains a url fragment (path), that is appended to existing url generated as follows: 'http://#{host}:#{port}/#{tomcat_root_url}' (simplified example).  Since the default is '/', the url generated matches exactly what it used to before the path was added.
#2 - if contains what appears to be a valid url, it is used instead, and the host/port properties are ignored (hence no longer required)

Username and password may also be encoded in the url, and they will be extracted, however it is recommended that the existing 'user' and 'password' params continue to be used so that security can be maintained w.r.t passwords
Merge branch 'master' of https://github.com/maestrodev/maestro-tomcat-plugin