TL: bump version to 5.5.2 + added release guide for maintainers (#489)

* TL: added release guide

* TL: additional detail

* Update 07_release_guide.md

* TL: minor correction on release guide

* TL: typo

* TL: lighter testing

* TL: bump version to 5.5.2

* TL: let's not care

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Co-authored-by: Robert Speck <[email protected]>

TL: dump version (#474)

Merge branch 'master' of https://github.com/Parallel-in-Time/pySDC

version bump

Merge branch 'master' of https://github.com/Parallel-in-Time/pySDC

Bump version

proper readme and link

NCCL communicators (#392)

* Added wrapper for MPI communicator to use NCCL under the hood

* Small fix

* Moved NCCL communicator wrapper to helpers

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Co-authored-by: Thomas <[email protected]>

NCCL communicators (#392)

* Added wrapper for MPI communicator to use NCCL under the hood

* Small fix

* Moved NCCL communicator wrapper to helpers

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Co-authored-by: Thomas <[email protected]>

Documentation ONLY(!) for `acoustic_1d_imex`, `testequation0d` and `v…

…anderpol` + fixed typo's (#341)

* Documentation for VdP, Acoustics, TestEquation + Typos

* One more typo