docker: libdl dependency

docs: improvements to the release doc

plugins: add support for plugin configs

* Adds missing items to ToC
* Adds sub-level items to ToC (there's not many, lets allow people to more easily skip to a section)
* Moves release process illustration to the top of the release flow section - it's an overview, it should be at the start not the end
* Fix a typo
* Removes braces in "Goal(s):" where there is clearly more than one

For now, configs specified in `daemon --init-config` and `init CONFIG` are not
available. We should fix this eventually but isn't necessary for now (and
supporting this will be annoying).

Update README.md

Removed OpenBSD line per discussion started with https://github.com/ipfs/docs/issues/254#issuecomment-526372366

doc: remove gmake instructions

This should now "just work". Calling `make` on non-linux platforms will invoke
`gmake` automatically and we now disable fuse on *bsd platforms.

feat: add ability to use existing config during init

doc: expand and cleanup badger documentation

feat: improve plugin preload logic

version: don't print 'VERSION-' if no commit is specified

fixes #6022

dep: update bitswap

fixes a bunch of lock contention.

dep: update deps

Fixes some unsafe uses of the "unsafe" package.

fixes a long-standing race condition

* Swarm: fixes data race.
* Datastore: make delete idempotent.

Update go-libp2p, fix tests with weak RSA keys

"identity" is the official name

We can no longer test this with bad keys. Unfortunately, good keys will likely
contain a newline and we have no way to send such keys to the server due to how
API requests are formatted.

dep: update blockstore + bbloom

Fixes several unsafety issues. Works towards #4485.

build: fix build on go 1.13

fixes #6603