4.5.1

• FIX HTML or plain text toggle works across PJAX requests (Robbie Averill) - afa4e75
• Use precise dist on Travis to ensure PHP 5.3 support (Robbie Averill) - 4adfc1b
• FIX Alias object context in closure for PHP 5.3 compat, add test to cover it (Robbie Averill) - fac99f7