RL10-C2 engine B9 subtype

[Starkillerdude]

I decided to include the -C2 subtype in the -B2 config. Performance increase is not that much but it would still be nice to have it.

here the whole config (convert to .cfg before use):

bluedog_CentaurD_RL10B2.txt

[Rodg88]

The stats irl should be identical, and now the rl10 variants are all merged an extra subtype would really need a good justification to take up space in the switch.