Use precise estimate of left-of-line offset in coordsChar
[javascript mode] Fix parsing of binary operators
[closetag add-on] Unbreak close-on-'/' behavior

Closes #1207
Use first-character tag of change origins to influence history event combining

Issue #1203
Add and document eachLine document-iteration method

Closes #1204
Fix calling charAt on undefined in previous patch

Issue #1203
Remove 'stop' argument from lookupKey's interface
Try to factor keymap code into something that can be used externally

Issue #1076
[htmlmixed mode] Clip script-type-finding slice start to zero

Issue #1209