Add MINIMIZE_QUOTES generator feature

[itzg]

One of the reasons I like yaml is the option to use very little quoting...so, selfishly, I wanted a YAMLGenerator feature to enable output that looks more like:

short: one line content
long: |
  line 1
  line 2

I left the default behavior as it is now, to use quoted string scalar style.

Please let me know if there are any associated changes, such as documentation, that you would like me to make.

[cowtowncoder]

Sorry about this -- I missed the update here. I'd be happy to accept this patch, seems useful. It will need to go in 2.7, being an addition to API.

One practical thing we need, before I can merge the patch, is filled Contributor License Agreement (CLA). A copy can be found here:

https://github.com/FasterXML/jackson/blob/master/contributor-agreement.pdf

and usually developers print it, fill + sign, scan and email it to info at fasterxml dot com.
If that works, it'd be great, and I can merge the patch ASAP.

Once again, thank you for the PR --- looking forward to merging it.

[itzg]

No problem at all. I have emailed my signed CLA.

[cowtowncoder]

Thanks again, just merged!