Update to latest portal, Taverna Server

Use newer portal from Bitbucket and Taverna Server 2.5.4

Remove SEEK configuration override. This may cause some emails and Google
Analytics to stop working, but need to find a more sustainable way to
enable these.

Split the Solr and worker init scripts so they can be done separately,
to allow database to be seeded correctly.

DRW modified to work with pathname taverna-commandline-2.* and also
taverna-commandline-enterprise-2*