* [chores] update README to new ink! 3.0 syntax

* [*] update all broken LICENSE and README.md symbolic links

* [*] update all license headers

Also be more strict about their dates: 2018-2020 for all

* [*] move all ink! crates into crates/ directory

* [ci] adjust .gitab-ci.yml to crates/ directory

* [ci] fix GitLab .gitlab-ci.yml (attempt #2)

* [ci] forgot some lines in attempt #2

* [examples] fix example smart contracts

They need to readjust their paths for the crates/ directory.

* [core] Factor nightly alloc parts out of core into new alloc ink crate

* Further cleanup after factoring out ink_alloc crate

* [alloc] Use symlinks instead of copies

Note: No other changes and renamings have been done yet so the crate is currently not in a compilable state.