Allow bundle to be used without clients or indexes defined.
Move type configuration into independent method
Refactor documentation
Add support for clients requiring basic HTTP authentication
fix some block comment
Bump symfony requirement
Updated changelog
Update Configuration.php

Updated to support any HTTP request header type in the "headers" section.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	Logger/ElasticaLogger.php
	README.md
Added notice about added support for HTTP headers.
Merge pull request #496 from rayrigam/master

Add support for clients requiring basic HTTP authentication
Make fetchSlice compatible with custom repo method

If a user configures query_builder_method for the doctrine provider, and
does not alias the root entity to equal Provider::ENTITY_ALIAS then a
DQL error will occur during index population.

> [Semantical Error] [...] near 'a.id ASC': Error: 'a' is not defined.

Provider::countObjects already handles this by dynamically fetching the
alias with QueryBuilder::getRootAliases, and Provider::fetchSlice should
be doing the same.

nb. "Provider" refers to FOS\ElasticaBundle\Doctrine\ORM\Provider
Unset fields if no nested fields are defined
Clone entities on delete to preserve ids
Prevent division by zero error
Merge pull request #514 from jvandesande/MultiField

Unset fields if no nested fields are defined
Merge pull request #505 from piotrantosik/fix_docblocks

Fix some block comment
Merge branch 'master' into documentation

Conflicts:
	DependencyInjection/Configuration.php
	README.md
Merge pull request #510 from peterjmit/master

Make fetchSlice compatible with custom repo method
Documentation updates