[B+C] Add Wake and Sleep API. Adds BUKKIT-3155

**The Issue:**
There is no way of waking players up, neither is there a way to put them in a bed.

**Justification for this PR:**
This feature was requested in the #bukkitdev IRC channel by a few plugin developers.

**PR Breakdown:**
Adds three new API calls to the Player Entity. 2 for sleeping, 1 for waking. Als adds a new Enum to allow checking if putting the player to sleep succeeded.

**Testing Results and Materials:**
This PR can be tested by the following test plugin: https://github.com/JadenKorr/SleepWakeTestPlugin

**Relevant PR(s):**
CB-953 - https://github.com/Bukkit/CraftBukkit/pull/953

**JIRA Ticket:**
BUKKIT-3155 - https://bukkit.atlassian.net/browse/BUKKIT-3155

**Pull Request Check List:**
*General*:
- [x] Fits Bukkit's Goals
- [x] Leaky Ticket Ready
- [x] Code Meets Requirements
- [x] Code is Documented
- [x] Code Addresses Leaky Ticket
- [x] Followed Pull Request Format
- [x] Tested Code
- [ ] Included Test Material and Source