Minor Research Table bug, Planet Utilization

Nothing really major and fixed in 2 seconds by modding, but given I've seen a few comments expressed on this around the boards, probably frustrates people a little.

Looking at the raw data, for 1.20 unmodded I found... that the Atmosphere Converter had a theoretical max level of 20, yet only ever made it to 2 in the game, so I looked at the tech tables and found that Planet Utilization tech was capped at lvl 21, so effectivly capped the converter at lvl 2. This makes for a horribly long time to convert planets. Only fix needed was to raise the Planet Utilization tech level max to 39 and it works.