Add a default "showitem" configuration

[davidsteeb]

It would be nice to add a default container showitem configuration for container elements that do not provide a more expansive showitem configuration.

When registering a new container this "showitem" TCA configuration could be added; as long as there is no special configuration set up following the registration of the container this default setup will be used. It would make sense to add default fields (like CType, language, access) to a default configuration so the container is working in most instances.

[achimfritz]

i would prefer "sys_language_uid,CType,tx_container_parent,colPos,hidden" as default configuration (tx_container_parent is required to place the container into an other container, cType colPos is required to place the container into an BE-Layout column) (? or?)

[ervaude]

Resolved by #29

[ervaude]

Wasnt merged yet :)