Disable charybdis’ connection throttling

Test the default channel list limit

fix #3219

Merge branch 'mam_default_limit' into 'master'

Limit of 100 MAM messages, if no other limit has been set by the client

Closes #3256

See merge request !9

Remove the flood limit in our e2e charybdis configuration

Test the TLS connection

Modify the charybdis conf to disable the LIST throttling

Provide a conf for charybdis