Update ELSP name

[aburrell]

Task: change "Equitable Letters for Space Physics" to "Equitable Letters for Space and Physics"

Reason: Initially we wanted to focus on the sub-discipline where we are, since that's where we can have the greatest impact. But many people who are connected and could take advantage of our resources don't see themselves as belonging to the "space physics" group. Changing the name to "Space and Physics" will probably solve that issue.