Use UUIDTools library.
BMFF::BinaryAccessor#get_uuid returns UUIDTools::UUID object.

BMFF::BinaryAccessor#get_uuid method returns an UUIDTools::UUID object instead of a binary string.
This change makes UUID handling easier.
Add BMFF::BinaryAccessor#write_uuid method.

Add the method in order to write UUID to file.
Add a function to parse UUID boxes.

BMFF will be able to parse 'uuid' type boxes.
Add a class which represents Protection System Specific Header box defined in PIFF 1.1.
Add the progress table for PIFF 1.1.
Fix a typo.
Add a class which represents Track Encryption Box defined in PIFF 1.1.
Fix comments.
Add a method to get the root object.

BMFF::Box::Base#root method returns my own root container object.
Add a class which represents Sample Encryption Box defined in PIFF 1.1.
Add a cache function to BMFF::Box::SampleEncryption.

In order to improve performance, BMFF::Box::SampleEncryption class will cache the Track Encryption object.
Declare DEFAULT_IV_SIZE.

Where is the track encryption box for the audio track?
Sample Encryption Box is supported.
Merge branch 'uuid' into develop
Change Travis CI badge URL for the develop branch.