Remove JSON::Parser as a dependency for the test suite

[hakonhagland]

JSON::Parser is no longer available on CPAN. It was removed from the JSON module in 2010, see this Changelog. Including it as a dependency for the test suite can cause the travis test to install the JSON module version 1.15 from 2007 (which includes JSON::Parser as a sub module). Incidentally this also installs an old version of JSON::PP (also included in the 2007 version of the JSON module) which can prevent the installation of a newer version of JSON::PP which again can cause test failures (see e.g. test t/104-filter_web.t) since the tests expect a newer version of JSON::PP to be installed.

I am curious if this patch will solve the failed test in PR #147 or if there is something else going on.

[coveralls]

Coverage increased (+0.4%) to 88.814% when pulling b3c9bcc on hakonhagland:json_parser into 3e87a4d on garu:master.

[garu]

Hi @hakonhagland! Thanks for the help trying to understand what is going on with that test failure, and for all the work you've been putting on the #74 PR (which I really hope gets merged soon).

Because Data::Printer is meant to help debug code, I feel a bit torn about removing support for a module, even if it's not on CPAN anymore. However, we do have tests for JSON::PP so I don't understand why we had separate tests for JSON::Parser if it was a submodule. Moreover, I don't understand why it would grok on a simple JSON string 😭

But I also feel like mining through BackPAN to try and figure out an error that's not even coming from Data::Printer, but from a filter that will (likely) rarely be used might be just too much work. So let's just do this and see what happens :)

Thanks again!