[haskell mode] Fix unintended prototype property access bug

Closes #1917
[real-world uses] Add Crudzilla
[closetag addon] Don't react to > and / keys when in an attribute

Closes #1916
[closetag addon] Another corner case when typing in attribute

Issue #1916
Merge branch 'master' of https://github.com/marijnh/CodeMirror
fix issue where selection would jiggle due to rounding issues