v0.9.0

• Usages of collections::Bound (which is deprecated) have been changed to ops::Bound. (@bstrie, #84)
• cron is now dual-licensed. Users can choose either the MIT or Apache 2.0 license.
• Schedule now has an includes() method. (@koenichiwa, #79)
• Schedule now implements PartialEq and Eq. (@koenichiwa, #78)
• Pattern fields that are * or ? no longer initialize a BTreeSet containing all possible ordinals. (@koenichiwa, #76)
• Schedule's internal representation was refactored to eliminate a workaround. (@koenichiwa, #75)
• Monolithic schedule.rs was refactored into smaller, more manageable modules. (@koenichiwa, #70)