Restore 1.8 legacy support

[linsaftw]

In collaboration of multiple server owners, we reintroduce 1.8 legacy support.

Still early and might have problems.

[linsaftw]

https://drive.google.com/file/d/1mDNGrw6_Eqx1T_LF6QQFhHU5LWFiCdx8/view?usp=sharing

[Xephi]

Hey, thanks for your contribution.
We may prefer an another module for these legacy build, so we can keep Fat Jar and Java 8 as far as possible of recents configurations.

[lokspel]

I really need 1.8

[linsaftw]

Done :)

[sgdc3]

@linsaftw I think what Xephi meant was adding a pre-1.16 maven module, not making the 1.16+ version compatible with 1.8

[linsaftw]

@linsaftw I think what Xephi meant was adding a pre-1.16 maven module, not making the 1.16+ version compatible with 1.8

@linsaftw I think what Xephi meant was adding a pre-1.16 maven module, not making the 1.16+ version compatible with 1.8

Thats what I did.

[sgdc3]

@linsaftw I think what Xephi meant was adding a pre-1.16 maven module, not making the 1.16+ version compatible with 1.8

@linsaftw I think what Xephi meant was adding a pre-1.16 maven module, not making the 1.16+ version compatible with 1.8

Thats what I did.

Yep sorry, I was distracted when I commented, the actual issue is that much of the "fallback" logic now is inside the core authme module, we would like to keep all the legacy listeners and fallbacks inside the 1.8 module.