MINIFICPP-910 - Extend StringUtils with string join capability

[arpadboda]

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[arpadboda]

The content of this file is mostly moved from the header, the changes I made were to make linter happy. Some of these functions still leave space for improvement.

[phrocker]

quite nice.

[phrocker]

I summarized my thoughts better in the ticket ( from my phone ) while watching a movie, so I'll let that stand.

[phrocker]

Thanks @arpadboda I'll launch this on some devices and merge if good.

As a project we generally don't commit dead production code -- but I can understand the desire to close this one out so I'll merge if it passes those tests. Thanks!

I think it's totally fair to leverage a need for code like this on others' pull requests as it begins a chain of testability.

btw, I don't suspect the builds to fail with this, but I perform these builds on anything in libminifi -- so I'll merge it when that is successfully complete, hoping in the next few hours. Thanks again!

[arpadboda]

@phrocker : thanks, usage will come soon! :)

[phrocker]

@arpadboda I hope to get this merged tomorrow. One of the builds passed, but the other devices are working on higher priority PRs.

raspberry pi 3 actually passes now on all variants of the OS so I think that one is good. Thanks! I'll check the other devices once those other PRs are finished building.

[phrocker]

just have one more platform to succeed. if it does I'll merge this. Thanks!