Instance request improvements

* One request per app start
* Request instance on logout
* Re-request instance on login
Formatting
Merge branch 'master' into fix/35/instance-logins

Conflicts:
	OpenTreeMap/src/org/azavea/otm/App.java
	OpenTreeMap/src/org/azavea/otm/rest/RequestGenerator.java
Merge pull request #43 from OpenTreeMap/fix/35/instance-logins

Instance & login request improvements