API Improvements

There are a couple inconsistencies within the API that should be relatively simple to fix.

## Filtering ConfigEntry Responses
The API always returns full ConfigEntry. It would probably be optimal to return only the requested parts, especially since the default frontend display will be the `routedParameters' field, and the expanded `ownParameters` or `parameters` fields will be displayed only on-demand.

## Inconsistent return types for PropertiesController
Some endpoints from PropertiesController return `text/plain` instead of `text/json` object. Which isn't very elegant.

## More routedParameters
Some items, such as weapons, have more vital info that is kept in lists (First, #1 has to be resolved) or other types, it would be great to find a way to route them and parse, so that they are neatly displayed. (i.e costume colors, icon colors, attack colors, attack particles)