Merging postreleasefix/81 to master
Merging postreleasefix/81 to master

* postreleasefix/81:
  Temporarily replace link to dynamic list of track hubs with static URL

Ensembl/ensembl-webcode,Ensembl/ensembl-webcode,Ensembl/ensembl-webcode,Ensembl/ensembl-webcode,Ensembl/ensembl-webcode