don't escape things unnecessarily

while it's not necessarily valid json it makes reading and
version-controlling json files easier to manage
correct po output

the string is not always ""
Automatically strip out translations which match the key as it makes it
easier to identify untranslated strings
enable Pot exports too
don't railroad settings

Unless explicitly defined, the defaults from the Translation class
should be used on export, and thecontents of the files used on import
read settings from the import file

Don't make the locale, domain, category defined in an translation
import/export file useless
Parse po file details from their location
correct param order for js translations
create directories on demand

It's tedious to need to create the directory for po files before writing
them
The filename is not the domain

the domain is _derived_ from the filename

Add the locale to the po file header too