Update changelog. 

v0.13 Wekan release. 

v0.12 Wekan release. 

v0.11.1-rc2 Wekan prerelease. 

v1.11.1-rc1 Wekan prerelease. 

Release 0.11.0-rc2 

Release 0.11.0-rc1 

Release 0.10.1 

Release 0.10.0 Closes wekan#425

Release v0.10.0-rc4