Fixed incorrect dates
Merge pull request #636 from karthik/master

Fixed incorrect dates for NorthWestern bootcamp
Add two workshops in Leeds, UK

These are both currently restricted but to a wide
group of people (all environmental scientists funded
by NERC - a major UK research funder - who are paying).
Merge pull request #637 from andreww/LeedsWorkshops

Add two workshops in Leeds, UK
Adding workshop for NHS MSc programme
Updated bio for Aleksandra Pawlik
Merge pull request #638 from apawlik/add-nhs-man

Adding workshop for NHS MSc programme
Merge pull request #639 from apawlik/update-aleksandra-bio

Updated bio for Aleksandra Pawlik
Adding badges for more instructors