Explicitly support nameWithLanguage and textWithLanguage values

[michaelrsweet]

Currently the IPP data file format used by ipptool and ippserver does not support language overrides for nameWithLanguage or textWithLanguage values, preventing testing of that part of IPP.

Ideally we should allow strings of the form:

"my string"(language)

[michaelrsweet]

Moving this to future since it will require more extensive libcups changes that upstream is currently not able to accept.