Generate `Automatic-Module-Name` attribute (#1375) (#1400)

* Generate `Automatic-Module-Name` attribute

As it stands, Java 9 Platform Module System cannot infer module
name from shapeless' jars due to cross compilation (underscores
in `_2.xx`).
This simple change adds an `Automatic-Module-Name` attribute to
MANIFEST, making it possible to require `shapeless` modules, rather than
going through various repackaaging hacks.
A proper modularization would include definition of `module-info.java`
but that's outside the scope.

* Use shapeless Java module name for core

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Co-authored-by: Hubert Plociniczak <[email protected]>

Bring README into line with org CoC (#1360)

Co-authored-by: Miles Sabin <[email protected]>

Shapeless 2.3.11

Shapeless 2.3.10

Shapeless 2.3.9

Shapeless 2.3.8

Restricted access to internals

Shapeless 2.3.7

Shapeless 3.0.0-M4

Shapeless 2.3.6