Two blocker issues for MP Config

[John D. Ament]

Unfortunately due to scheduling issues, I haven't been able to attend the config call.

I have two tickets that IMHO are blockers for the next release, one is a bug I'm seeing in Hammock and the other is an integration issue that has me stuck on Apache Safeguard.

https://github.com/eclipse/microprofile-config/pull/266

The synopsis: When you try to explicitly set the config provider (prior to booting an application) prior to application bootstrapping, that instance is not used because the static field has already been set.  The proposed work arounds from Ondrej don't work in this case (have tested it).  I'd like to get some ideas on paths forward to resolve this.

https://github.com/eclipse/microprofile-config/issues/267

For some reason, I thought already raised a PR.  I will do so shortly.  Basically, MP Fault Tolerance expects a class converter to be available to read exception types (note: the FT spec doesn't define the string format).  Rest Client also has this need for provider look ups.  Without this defined in a central point, I see two issues growing:

- Duplicate converter impls for class type (where each component impl needs to provide it to pass the TCK)

- Inconsistent format of the string values

[Emily Jiang]

Hi John,

#266 is an existing issue, which was reviewed in Hammock. We can discuss it more next week. I'll schedule a call to discuss this on Tuesday. However, even if we cannot resolve it on Tuesday/Wednesday, this should not block the 1.2 release as it is an existing issue, though we will try harder to get it resolved. I had hoped you shouted it aloud earlier. A doodle pool is to be announced soon.

#267 should have been fixed by the array support I added in via #259.

Thanks
Emily