Adding tests/fixes for possible XSS injections in view helpers

Signed-off-by: Marco Pivetta <ocramius@gmail.com>
[ZF2014-03] Added detail to README.md
Merge branch 'security/zf2014-03'

ZF2014-03 fixes
[2.3.1] Release readiness

- Updated README with version, date, and changelog
- Updated CHANGELOG with 2.3.1 and 2.2.7 details
- Updated version constant to 2.3.1
Merge branch 'releases/2.3.1'

2.3.1 release readiness
Release bump: 2.3.2dev
Merge branch 'release/bump'

2.3.2dev