Get rid of ServiceRegistry::getPropertiesService references in Mantis Codebase

Context

ServiceRegistry is a singleton instance that holds a reference to MantisPropertiesService. Several components within Mantis use this reference to get certain configuration values at runtime. There are several issues with this approach. Firstly, singletons take a lot of work to manage and test. Secondly, the way the MantisPropertiesService gets loaded is not extendable. We need to consider a more long-term approach to deal with dynamic properties within Mantis. Something like archaius2 might be a good idea.

Goals

1. Getting rid of ServiceRegistry.
2. Clean ways to integrate with various dynamic config implementations.