Merge pull request #3279 from alphagov/timlb-humans

Add Tim LB leaving message

public/humans.txt

@@ -1,2 +1,16 @@
 GOV.UK is built by a team at the Government Digital Service (with thanks to Martha!) in London,
 Bristol and Manchester.  If you’d like to join us, see https://gdscareers.gov.uk/
+
+Today we say a fond farewell to Tim Leighton-Boyce, a pillar of the GOV.UK Performance Analyst
+community. Tim leaves after a marathon shift as Senior and then Lead PA. Some say that only an
+analyst of his calibre could measure a time period that long without encountering rounding
+issues.
+
+In his early days Tim was an advocate of A/B testing on GOV.UK and taught many of us more about
+statistical significance than we thought we needed to know. More recently, he's been unpicking
+the complexity of updating our analytics software, which is no mean feat. Tim's worked on many
+of our most important products over the years, and has been a crucial part of making GOV.UK
+better.
+
+Tim's been an absolute pleasure to work with. His calm, quiet, excellence and friendly smile
+will be impossible to replace. Good luck skating off into retirement, we'll miss you!