[avatar] supported file extension in upper case
[avatar] supported file extension in upper case

miurahr/seahub,madflow/seahub,madflow/seahub,Chilledheart/seahub,Chilledheart/seahub,cloudcopy/seahub,Chilledheart/seahub,madflow/seahub,Chilledheart/seahub,cloudcopy/seahub,madflow/seahub,Chilledheart/seahub,cloudcopy/seahub,madflow/seahub,cloudcopy/seahub,miurahr/seahub,miurahr/seahub,miurahr/seahub