Support for PhotosetPost

[#5]
Fix compiler warning (Generics/Serialization/Unused vars) and Organize Imports
Some clean up for performance and code practices (correctness etc) -- FindBugs
Added support for notes
Minor changes - removed a useless comment and some whitespace
Replaced tabs with spaces
Replaced a tab with spaces
More whitespace changes
Edited Post.java to handle concers about copying and nulls

Maddalab suggested (https://github.com/tumblr/jumblr/pull/21/files#r5741882) that because I didn't actually use the reflection, it would be better to use System.arrayCopy. jay-to-the-dee suggested (https://github.com/tumblr/jumblr/pull/21/files#r5763924) that when notes is null, it would throw a NullPointerException. I believe I have fixed both of these issues.
Updated Post.java

System.arraycopy does not have an uppercase C. Thanks to jay-to-the-dee for finding this (https://github.com/tumblr/jumblr/pull/21#issuecomment-22645805).
Add original size attribute to Photo objects
Add author to Post objects
Add thumbnail info to VideoPost objects
Add getSlug() to Post
Use https for requests
Merge pull request #30 from benblack86/master

Ability to override default hostname
Added test for getFollowersCount
Merge branch 'master' of github.com:tumblr/jumblr
Clean up some indentation
Add exception tests

Pretty rudimentary for now, but better than nothing. Test what happens
when RequestBuilder methods throw JumblrException: all of them can.