Added delivery priority to the ApnsPushNotification interface and associated classes.
Added a first pass at a binary notification format encoder.
Added binary notification support to the mock server. One test is (rightly) failing at this point.
Send the sequence number as soon as possible so rejections are more likely to correctly identify the problematic notification.
Removed some unnecessary operation counter manipulation.
Start the sequence number count at 1 to avoid collisions with "unknown sequence number" rejections from the gateway.
Merge branch 'master' of github.com:relayrides/pushy into binary_notification_format

Conflicts:
	src/main/java/com/relayrides/pushy/apns/ApnsConnection.java
Assume an immediate delivery priority if the priority is null.
Added a copyright header and (trivial) docs to the ApnsFrameItem enumeration.
Merge branch 'master' of github.com:relayrides/pushy into binary_notification_format
Merge branch 'master' of github.com:relayrides/pushy into binary_notification_format
Merge branch 'master' of github.com:relayrides/pushy into binary_notification_format
Moved `ApnsFrameItem` into `ApnsConnection`.
Merge branch 'master' of github.com:relayrides/pushy into binary_notification_format

Conflicts:
	src/main/java/com/relayrides/pushy/apns/ApnsConnection.java
Dropped mock server support for ENF.
Used a more appropriate type for frame item component sizes.
Standardized on "delivery invalidation time" instead of "expiration."
Merge pull request #64 from relayrides/binary_notification_format

Binary notification format (closes #35)