Rename Zemanta to Outbrain

[rokostik]

Hey!
This PR renames the Zemanta adapter to Outbrain. We only want Outbrain to be seen to publishers so the biddercode and naming in the source code stays the same.

[bretg]

Sorry, but you're going to need to make some code changes before this is going to work. The docs name and the actual code name need to align. You have two choices:

1. rename https://github.com/prebid/Prebid.js/blob/master/modules/zemantaBidAdapter.js to outbrainBidAdapter.js
2. add 'outbrain' as an alias in zemantaBidAdapter.js (see appnexusBidAdapter for an example) then add an aliasCode header to this doc file. See districtm.md here for an example.

[rokostik]

Hey @bretg, thanks for helping and providing the instructions on how to properly implement this.
We went with option 2 and the code PR is located here: prebid/Prebid.js#6203.

[bretg]

Please note that by renaming this file, any customer that currently uses 'zemanta' will no longer see the biddercode on the docs site. If that's ok with you, this should work.

If you have customers using the zemanta bidder code, then you should consider having both outbrain.md and zemanta.md

[rokostik]

Hey @bretg, since pbjs was released yesterday can you merge this into master? Thanks!

[bretg]

part of 4.24