turned off overscroll on login screen. kind of sucks
Revert "turned off overscroll on login screen. kind of sucks"

This reverts commit fb9cdb43f7d7698dc58db92f1aca033bb560363c.
shrank tabcat logo on login page by 2/3 so password prompt shows above keyboard (fixes #163)
Merge branch 'master' of github.com:UCSFMemoryAndAging/tabcat
use $ for variables containing elements
keep entire login form above the keyboard on iPad