Pass maxProviders to content routing

[jacobheun]

With libp2p 0.24 you can now pass options objects to findProviders. The latest dht updates also include support for maxProviders.

This updates the call to findProviders so that both the maxProviders and maxTimeout options are sent.

Libp2p 0.24 will be in the js-ipfs 0.34 release, so we should be able to get this update in there as well.

Also in this PR:

• Update dependencies, also use libp2p-mplex instead of libp2p-multiplex
• Fix linting as a result of the latest Aegir
• Drop non jenkins ci files
• Remove .npmignore in favor of package.json files attribute
• Change tests to use 512 instead of 1024 keys, we dont need 1024 for testing

The bit change to the key reduced the test:node time locally quite a bit:
Before

real    0m39.634s
user    0m26.516s
sys     0m1.095s

After

real    0m24.447s
user    0m11.426s
sys     0m1.023s

[vmx]

Can we please keep the pre-push testing. I think they run fast enough so that it is OK.

[jacobheun]

Added that back.

[vasco-santos]

Looks good to me! 👍

[vmx]

Thanks for also taking care of updating the deps and fixing the linting errors.