extend dynamodb2.table.query_count for more args
add simple test for query_count
Add method TaggedEC2Object.add_tags().

There is already a TaggedEC2Object.add_tag() method but it only supports
adding one tag at a time. The CreateTags api supports adding multiple tags
at once. So, when you want to add multiple tags you needlessly make multiple
round-trips to EC2 service. The add_tags method helps in avoiding that.
Fix behaviour of remove_tag when empty string is provided as value.

The documentation says that there is a distinction between a
value of '' and a value of None. The API docs say the same
thing. But the code was not following the docs:
    if value:
returns False for both None and ''.
Add tests for add_tag, add_tags, remove_tag methods of TaggedEC2Object
only attempt shared creds load if path is a file
Merge pull request #2305 from raphaellig/shared-credentials-load-fix

Only attempt shared creds load if path is a file. Fixes #2305.
Update failing test
Add multipart upload section to S3 tutorial
Merge pull request #2308 from danielgtaylor/multipart-tut

Add multipart upload section to the S3 tutorial. Fixes #2308.
get_all_networkinterfaces() - add param to restrict lookup by list of ENIs
add update(), attach(), and detach() methods
add eni unit tests
s/existance/existence/
Add documentation for delete_hosted_zone.

Added documentation for delete_hosted_zone and add return type documentation for get_zones.
Merge pull request #2315 from jianli/develop

s/existance/existence/
Merge pull request #2316 from ttacon/develop

Add documentation for delete_hosted_zone. Fixes #2316.
Parse date/time in a locale independent manner

Creates a new threadsafe context manager to temporarily reset locale so that
strptime behaves as desired. Fixes #2271.
Reset locale after test run
Merge pull request #2317 from danielgtaylor/ts-locale

Parse date/time in a locale independent manner. Fixes #2317, #2271.