Fix error in test
Merge pull request #239 from Ghost141/npm_test_fix

Fix error in test
Fix error in update user profile test.
Merge pull request #241 from Ghost141/npm_test_fix

Fix error in update user profile test.
Fix test error in test.marathonChallenges.js
Merge pull request #242 from Ghost141/npm_test_fix

Fix test error in test.marathonChallenges.js
Update Challenges API

1. Update api doc.

2. Update Active/Upcoming challenges API to return all challenges at once.

3. Refactor challenges queries.
Merge pull request #243 from Ghost141/challenges_api_update

Update Challenges API
Fixed query logic.
Remove private parameter in challenges api.
Merge pull request #244 from Ghost141/challenges_api_update

Remove private parameter in challenges api.
fix phase id for getting user rating
allow TC Staff to access the documents field in challenge Detail API
Merge pull request #238 from LazyChild/update_billings

Add 'startDate' and 'endDate' for creating billing.
fix time format in reg success email
update billing when 'billingAccountId' is given.