JSON stream support

Main focus has been to expand from just the use-case of accepting a single JSON document, and unpacking arrays to NDJSONifying JSON streams in general. So a stream of objects will usually just be converted to NDJSON. Also because the default is to unpack an array we now have an option that says you don't want that which allows you to preserve arrays -preseve-array.

Aside from that small improvements, like a friendlier error message in some circumstances.

Full Changelog: v0.3.2...v0.4.0

v0.3.2 - Faster key scanning

• Faster at finding keys in objects (for -path).
• Improved (non array) EOF error.
• Improved version reporting for go tool builds.

v0.3.1 version reporting

You can now ask json2nd what version it is:

json2nd -version

Although at present you only get a useful response from the github builds.

v0.3.0 minor improvements

• buffered output for some very slight performance improvement (in some circumstances).
• fix: output status 0 on failure.

v0.2.0 - incremental progress!

• Added detection of objects that don't finish before the end of a file.
• internal improvements and more testcases.

v.0.1.0 - it basically works!

Basic functionality works.