Add Ubuntu-20.04 Focal install capability

[ansell]

There are a few locations where Ubuntu version specific tasks or variables are defined. Need to add Ubuntu-20.04 to those cases as possible to enable installations to proceed on Ubuntu-20.04

• [x] Add Ubuntu-20.04 (Focal) install capability for biocache-service as a first test
• [x] Test the Living Atlases demo to identify issues installing on Ubuntu-20.04 (expecting issues with Tomcat-9 and MySQL-8.0)
• [x] Issue identified with MySQL-8.0 and logger-service define_user.sql syntax issue (tracking in #390):

  TASK [logger-service : create schema, stored procs and reference data] *********
  changed: [living-atlas.org] => (item=/tmp/schema.sql)
  changed: [living-atlas.org] => (item=/tmp/eventLogType.sql)
  changed: [living-atlas.org] => (item=/tmp/reasonLogType.sql)
  changed: [living-atlas.org] => (item=/tmp/sourceLogType.sql)
  changed: [living-atlas.org] => (item=/tmp/refresh_summary_breakdown_email.sql)
  changed: [living-atlas.org] => (item=/tmp/refresh_summary_breakdown_reason.sql)
  changed: [living-atlas.org] => (item=/tmp/refresh_summary_breakdown_source.sql)
  changed: [living-atlas.org] => (item=/tmp/refresh_summary_totals.sql)
  changed: [living-atlas.org] => (item=/tmp/update_breakdown_summary_information.sql)
  failed: [living-atlas.org] (item=/tmp/definer_user.sql) => {"ansible_loop_var": "item", "changed": false, "item": "/tmp/definer_user.sql", "msg": "ERROR 1064 (42000) at line 2: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'identified by 'logger_user' with grant option' at line 1\n"}

[ansell]

Installation scripts execute on Ubuntu-20.04. Opened a separate issue for the MySQL issue that is causing the demo to break.