KDU-414 should be renamed to S5.19

[Fawnnia]

The S5.19 is the name for the engine on the KDU-414 unit and should be renamed, as the KDU-414 refers to the propulsion unit and not the engine itself.

[Clayell]

I believe there was a discussion on this a few weeks ago, and some valid points were brought up.

njits23: The KDU-414 is a combo of the S5.19 engine with fuel. Are there any other engines (other than solids) that come with their own fuel?

ReaBean: Then shouldn't the engine in game be renamed? If the KDU-414 name talks about more than just the engine

njist23: I don't think it was ever used without its tank.

ReaBean: Hmm, i mean the one in game doesn't come with a tank, and the engine itself has a name seperate than the KDU-414 Then it might be good to rename? What are your thoughts?

Katniss: imagine if they named the J-2 `S-IVB`

Clayel (replying to njit23's second comment): i mean to be fair, most engines do require fuel to operate 👀

I think I agree with Katniss's point the most, where parts should be named after the engine itself, not the fuel tank that comes with it, as it would ridiculous to call other engines by their fuel tank names. While I do think the S5.19 is more integrated with its fuel tank than most other engines (similar to the Centaur, and we still differentiate between it and the RL-10), to a certain point all engines are specifically designed to work with their specific rocket, and changing the rocket design usually requires changing the engine inlet design slightly. I will submit a PR to fix this.

[Fawnnia]

I saw the discussion too, Reabean is me. Looking further the engine on the initial KDU-1 used the S5.9 engine. The S5.19 was used on the 2MV Venus probe.

The KDU-414 for the Molniya satellites mainly used the S5.31 engine.

It might be worth it to add configs to the engine starting at the S5.9 ( if data is available ). Heres what I was able to find:

https://web.archive.org/web/20210723221009/https://b14643.de/Spacerockets/Specials/KB-Isayev_KDUs/index.htm

[Clayell]

Why did the russians have to make 5000 different engines? Astronautix says "KTDU-414;S5.19", so idek.
If we can get performance data for all of the engines, lets do it.