update composer

[bidi47]

remove packages from root composer.json if they are are already required by other packages

[bidi47]

removed packages
dotkernel/dot-event - required by dotkernel/dot-mail
dotkernel/dot-helpers - required by dotkernel/dot-navigation
dotkernel/dot-log - required by dotkernel/dot-errorhandler
dotkernel/dot-rbac - required by dotkernel/dot-rbac-guard
mezzio/mezzio - required by dotkernel/dot-errorhandler

[arhimede]

fix dot-errorhandler
and add back here mexxio/mezzio

[bidi47]

dot-errorhandler is updated - we should review and make a new release
added mezzio/mezzio in #257