Fixes for OSX compliation

[codeadict]

Fixes #1391

This PR adds:

• Temporarily upgraded to my personal branch of eleveldb, until filled a PR at Modernize to build on OSX and other envs easier eleveldb#5.

• Fix for OSX compilation due to recent Homebrew changes that added OpenSSL 1.1 and deprecated 1.0, this new way will ensure that compilation always use the latest OpenSSL installed by Homebrew, making it more resilient to changes. Still could be issues on systems that had the previous OpenSSL version and static libraries are still hanging around (The error looks like dyld: Library not loaded: /usr/local/opt/openssl@1.1/lib/libcrypto.1.0.0.dylib), the best on this case is to run:

$ brew update
$ brew uninstall --ignore-dependencies openssl
$ brew install openssl

[ioolkos]

@codeadict thanks! :)

@dergraf, @larshesel how and when should we merge this?

[codeadict]

I see Travis is failing, I'm gonna test on a Linux machine today to see if I broke something. Can't easily find any clue on Travis logs.

[codeadict]

This is passing now, had to install the snappy-dev headers, i'm wondering if this requirement will be an overkill and we can just keep snappy in the repo but with the most recent version. Thoughts @larshesel @dergraf

[dergraf]

He @codeadict thanks for the contribution. I think we should wait with merging until your PR vernemq/eleveldb#5 is merged and then point to the vernemq/eleveldb repo instead of your fork.

[codeadict]

You are right @dergraf , I'm still working on Adding CI to eleveldb so we know when things break and can have full confidence that it can compile in OSX all the time. The old Travis config is from the Basho days and was not working at all

[codeadict]

@dergraf - vernemq/eleveldb#5 is now ready for your feedback

[codeadict]

I'll go ahead and point the package to the official vernemq one instead of my fork tonight.

[codeadict]

This is ready now @ioolkos @larshesel , seems like an unrelated test is failing. Can you please take a look.

[ioolkos]

@codeadict great stuff, this seems to need a rebase, then we should be able to merge.

[codeadict]

@ioolkos - All rebased now.

[codeadict]

Closing in favor of #1423