Fix HTTP timeouts for SSL connections

CertValidatingHTTPSConnection did not implement the http.HTTPConnection timeout argument correctly.  Newer Botos appear to use this connection instead of httplib.HTTPSConnection which breaks the [Boto]/http_connection_timeout configuration setting.

This patch sets the timeout on the new SSL socket if it has been configured.
Make proxy_ssl used configured timeout

The proxy_ssl method does not use the Boto [Boto]/http_connection_timeout setting when creating its socket.  This patch will configure the requested timeout if it is set in the http_connection_kwargs parameter.
Initial support for network acls
get_all_network_acls now works properly
Removed extraneous comments.
Added support for associating and disassociating network ACLs and
subnets.
Added supoprt for replacing network acl entries.
Now properly populates NetworkAclEntry class with icmp & port range
options.
Removed unnecessary import of NetworkAclEntry.
Give vpc objects an update method to update state
Added some unit tests to cloudsearch
Merge remote branch 'origin/develop' into cloudsearch_unittests
Added more unit tests for cloudsearch
refactored cloudsearch connection unittest class and added more tests
Added boto.cloudsearch.layer1.Layer1.index_documents() test
Added EBS information to the EC2 tutorial
Fixed up sphinx warnings in elastictranscoder inline docs
Fixed up sphinx warnings in fps inline docs
Re-implemented cloudsearch connection tests using AWSMockServiceTestCase
Fixed up inline docs for boto.rds.dbsecuritygroup.DBSecurityGroup
Added a basic RDS tutorial