Fix for issue #56 :: added ENT_COMPAT to one-liner meta box value

This fixes the issue by changing the ```htmlentities()``` flag argument to ```ENT_COMPAT``` instead of ```NULL``` on the one-liner postmeta box display. According to the php manual, ```ENT_COMPAT``` will *convert double-quotes and leave single-quotes alone*. This seems to be desired behavior, and allows for shortcodes and other quote-containing strings to be used properly in one-liner content blocks.