Refactoring Client.getApplication().
Refactoring Client.getApplication().

Adding jsdocs / cleaning up code.

stormpath/stormpath-sdk-node,wakashige/stormpath-sdk-node,peebles/stormpath-sdk-node,stormpath/stormpath-sdk-node,peebles/stormpath-sdk-node,ck-lee/stormpath-sdk-node