Add escapeGt option for HTML/XML encoders

[Former user]

Original [issue 209](https://code.google.com/p/okapi/issues/detail?id=209) created by @ysavourel on 2012-02-14T22:02:46.000Z:

Allowing to escape greater-than in the output after merge is useful for several users.

See http://tech.groups.yahoo.com/group/okapitools/message/2632 and http://tech.groups.yahoo.com/group/okapitools/message/2644

[Jim Hargrave (OLD)]

HTML filter implements quotemode in encoder