Make pattern encoder default #266

[agentgt]

The pattern encoder was never set as the default encoder but the jansi encoder was making configuration confusing.

The jansi encoder is pretty worthless as you cannot configure it and I mainly added it just to give rainbow gum some initial color.

The jansi encoder will be removed in the long run (jansi will stay for ansi safe output though).

There is a default encoder called TTLL always shipped with core rainbow gum that now can be accessed through URI schema.

I made it easier to register a TTLL encoder which is used if no other encoders are found / not specified. This should be separated out as different work but oh well it got put in this change.

I also found some missing Spring Boot colors while looking at the ANSI stuff in pattern module. Again probably should be separate issue.