Support for Basic Authentication and HTTPS

[nkvoll]

Many people use Elasticsearch over unsecured networks that requires encryption and authentication.

Added support for connecting to HTTPS servers and authenticating via basic auth.

from elasticsearch import Elasticsearch

dc = Elasticsearch(["secure-server.com:443"], transport_schema='https', auth='user:password')
dc.search()

from elasticsearch.connection.http import RequestsHttpConnection

rc = Elasticsearch(["secure-server.com:443"], transport_schema='https', auth='user:password', connection_class=RequestsHttpConnection)
rc.search()

Theres a few failing tests on test_elasticsearch.test_connection.TestRequestsConnection, which is caused by the mock object used in the tests not being set up to handle actually being merged with the session config.

If this is an acceptable API, the tests can of course be fixed, but awaiting feedback before spending time on it.

[honzakral]

This has been fixed in 7a440fd and b724288

Thanks for the patch, I used a lot of the code.

[nkvoll]

That's great! As you're part of the Elasticsearch team, is a similar change possible for the rest of the clients (ruby/php/perl) too? I'm sure their users would benefit from https and auth support as well, and if the APIs could be kept similar, that's an obvious benefit :)