Make Twitter::Place#id attribute accessible

Closes https://github.com/sferik/twitter/pull/544.
Enable injection of custom TCP/SSL socket classes.

Twitter::Streaming::Client class now accepts custom TCP/SSL socket
classes. It passes those along to Twitter::Streaming::Connection.

It's possible to inject non-blocking sockets this way, which in turn
makes it possible to use Twitter::Streaming funcitonality with
Celluloid. The Connection class blocks the Actor's mailbox otherwise.
Deprecate predicate methods without question marks
Enable injection of custom TCP/SSL socket classes.

Twitter::Streaming::Client class now accepts custom TCP/SSL socket
classes. It passes those along to Twitter::Streaming::Connection.

It's possible to inject custom sockets this way, which in turn
makes it easy to use Twitter::Streaming funcitonality with
Celluloid::IO.

Celluloid's Socket classes support both blocking and non-blocking
operations.

https://github.com/celluloid/celluloid-io/wiki/Using-Celluloid::IO-with-existing-Ruby-libraries
Proper rspec matchers used in specs.
RuboCop's suggestions implemented.
Merge branch 'injectable_connection_sockets'

Conflicts:
	lib/twitter/streaming/connection.rb
	spec/twitter/streaming/connection_spec.rb
Changed names of *_socket_klass to *_socket_class.
Merge pull request #546 from neektza/injectable_connection_sockets

Enable injection of custom TCP/SSL socket classes.
Fix RuboCop offenses introduced in version 0.20.0
Update http dependency to ~> 0.6.0
Deprecate Twitter::Base#[]
update docs to match API, fix discrepancy
Merge pull request #552 from muffinista/user_docs

update docs to match API, fix discrepancy
Remove statement that TweetStream is not 2.0.0-compatible

This has been fixed since the 2.6.0 release, see:
https://github.com/tweetstream/tweetstream/blob/master/CHANGELOG.md#version-260
Merge pull request #553 from mrgilman/remove-inaccurate-documentation-re-tweetstream

Remove statement that TweetStream is not 2.0.0-compatible
Fix missing link to TweetStream
Merge pull request #554 from mrgilman/mg-fix-tweetstream-link

Fix missing link to TweetStream
Dont allow unacceptable IO objects in update_with_media

We ran into a bug where a 401 error was returned for any File-like
object that didn't have a to_io method defined
(ActionPack::HttpUploadedFile in this case).

Since the contract of this object is to have a to_io method otherwise
it will be included in the oauth signature (cause of 401) then we should
short circuit early on when we know this is supposed to be a File like
object. Later on we aren't sure exactly when we include/exclude params
from the signature.
Fix style guide violations (bundle exec rubocop)