[js] Optimise setlimit tomark AE for ...
[js] Optimise setlimit tomark AE for ...

All uses of setlimit in the current stemmers we ship follow this
pattern, and by special-casing we can avoid having to save and restore
the cursor.

Addresses https://github.com/snowballstem/snowball/issues/74 for
Javascript.

snowballstem/snowball,snowballstem/snowball,snowballstem/snowball,snowballstem/snowball,snowballstem/snowball,snowballstem/snowball,snowballstem/snowball,snowballstem/snowball