v2.1.0-beta.13

1. a thread can be only viewed by its author or admin users
2. refine the interface of group edit and tag edit

v2.1.0-beta.12

1. fix unable to modify user

v2.1.0-beta.11

fix removing test case

v2.1.0-beta.10

fix testcase url

v2.1.0-beta.9

fix removing group

v2.1.0-beta.8

fix login and creating group

v2.1.0-beta.7

fix: fix password invisible in contest edit mode

v2.1.0-beta.6

fix being unable to add a new contest

v2.1.0-beta.5

fix status page loading

v2.1.0-beta.4

fix group/tag edit page error