Fixes regarding hide_fps_superscript in horizontal mode and fps_metrics component.

[JustCryen]

Fixing new inconsistent behavior implemented during a rewrite e96a0bf
Which is, with horizontal mode enabled and long names selected (lacking engine_short_names in the config), fps superscript remains hidden (even without the use of hide_fps_superscript) and engine name is replaced with an "FPS" text.
This shouldn't happen when user prefers a long engine name to be present.

Additionally addressed issues provided by @ChrisLane discussed in pr #1821 related to a feature implemented in pr #1751.

1. FPS superscript still appears for FPS stats in the fps_metrics component.
2. hide_engine_names does not override engine_short_names so if the latter appears in config, the former will not take effect.

1. I figured out how to get the hide_fps_superscript to influence the superscript in the fps_metrics component. […]
2. […] it seems like this point is already taken care of. hide_engine_names with or without engine_short_names does show just the big FPS text, and hides superscript in the main FPS meter in the process, but also disables the superscript in the fps_metrics component.
   Let me know how this should be handled.

[JustCryen]

A test might be needed for the fps_metrics component, I'm not generally using it, so I had just a quick and dirty test conf file.
I might have missed something.