Feature: LDC-251 - contest & contest entry node views

## Ready State: Yes

This pull request is related to the following JIRA tickets:
https://imagex.atlassian.net/browse/LDC-251

Contest nodes use panelizer to allow admins adjust displays based on whether the contest is open to entries/voting or has finished. Default pane visibility settings mean the default layout should be sufficient in most cases.

Contest Entry nodes use the default node view but have classes injected if they are selected as finalists or winners to allow some variation in the theming:
* node-contest-entry-finalist 
* node-contest-entry-winner

## Requirements & Dependencies

None

## Deployment Instructions

* Merge code.
* Enable imagex_contest & imagex_contest_permissions
* Clear caches with `drush cache-clear all`

## Usage/Test Instructions

* Create a contest node and ensure:
  * Default panelizer layout is shown
  * Selecting an entry as a winner or finalist (via node/NID/contest) makes them show on the contest node view
  * Closing entries hides the "Entries Deadline" from display
  * Closing voting hides the "Voting Deadline" from display
* Create a contest entry node and ensure:  
  * When selected as a finalist or winner that additional classes (node-contest-entry-finalist, node-contest-entry-winner) are added to the wrapper div.node 

#### NOTES

* I simplified this to hit the deadline
* Voting functionality will be covered in https://imagex.atlassian.net/browse/LDC-259