add Rest web service

UserService :
- user/login_check
- user/register
- user/user_detail
- user/update_profile

TaskService :
- task/task_detail
- task/delete_tag
- task/delete_comment
- task/delete_assignee
- task/update_task
- task/finish_task
- task/delete_task
- task/get_category_task

CategoryService :
- category/get_list
- category/delete

Details can be viewed in
https://docs.google.com/spreadsheet/ccc?key=0Aimdv_92Ymo3dGZkSVZqSmhvZDBueENxaDNxTEFnN3c#gid=0