At request page, Admin can accept, reject the request
Merge pull request #48 from huyen123/task#4279

At request page, Admin can accept, reject the request
Task #4362 Admin can set a request's status to Finished
Merge pull request #49 from trungquan/Task#4362

Task #4362 Admin can set a request's status to Finished
Task #4354 Create a function to calculate the interval days between two date