Don't use error suppression on realpath() + style adjustments
Don't use error suppression on is_dir(), file_exists()
More removal of error suppression usage
Deprecate HTML helpers nbs(), br()
Call db_connect(TRUE) instead of db_pconnect() + some style changes
Add  parameter to CI_Input::user_agent()
Fix #2916
CI_Encryption: Remove MCrypt 'work-arounds' for CAST-128 compatibility

Turns out it's OpenSSL's fault for performing 16 rounds instead of 12 for key sizes of 5-11 bytes.
Reference: http://tools.ietf.org/rfc/rfc2144.txt
Add support for simpler (Callable) hooks (issue #2917)
[ci skip] Fix a test skip message
Fix #2919
Add support for callable form validation rules
Fix #2928
Re-enable hhvm/mysqli tests
Fix #2928, #2929