[Persistence] Explicitly refresh bootstrap cache when new user added

Addresses nasa/mct#245 by explicitly refreshing the cache of bootstrap components when a new user is added to Persistence; failure to do so permits a slightly out-of-date cache of these components to be furnished to the User Environment, meaning that the freshly-created My Sandbox is not visible to the user at startup.

```
 Wrote or re-wrote unit tests (Y/N): Y
 Ran entire suite of unit tests successfully (Y/N): Y
 Verified bug fix with the described replication steps or verified the implementation meets the requirement cited (Y/N): Y
 Code coverage requirements satisfied (new code=80%, changed code=at least as high as existing) (Y/N): Y
 Code review date and attendees: Self-review by pull request
 Describe potential impact on other areas of the code: Persistence, start up
 Describe any test prerequisites for this fix (e.g., restart the database): Run platform using Derby without existing database, and automatically.add.user enabled
 For bugs marked "Regression - Yes", describe the cause of the regression: See below*
 Did you modify any pom.xml file? If yes, did you thoroughly document your changes and reasons? N
```

*Failure to include a cache refresh on add user when step-behind caches were added in nasa/mct#232 (some cases were addressed in nasa/mct#233, but persistence's add new user circumvents these)