Remove @EnableAutoConfiguration from autoconfigure tests

It was doing scary things (like starting elasticsearch, hornetq etc).
There's still an outstanding question about why the context was
not being properly closed in such a scenario (maybe one of those
embedded servers lurking on a background thread?).

See gh-1034
Polish DataSourceInitialization code

Rename a few classes and methods relating to DataSourceInitialization
and update the DataSourceInitializedPublisher to check for Hibernate
settings.
Polish documentation

Apply consistent styling and edit a few section for clarity.
Add gmavenplus-plugin to parent POM
Convert README.md -> README.adoc
Polish ConditionalOnJava

Apply formating and simplify the condition implementation. Delegate
to Spring's JdkVersion class to obtain the running version.
Polish Flyway and Liquibase

Extract common "depends on" functionality to a new
EntityManagerFactoryDependsOnPostProcessor class.

Apply consistent formatting.

Fix issue with Flyway location detection.
Polish
Improve Spring Mobile Auto-configuration

- Upgrade Spring Mobile dependency to 1.1.2
- Rename SitePreferenceAutoConfiguration "enabled" property
- Add Auto-configuration for LiteDeviceDelegatingViewResolver
- Update docs

Fixes gh-1049
Add ProviderSignInController for Spring Social

Update SocialWebAutoConfiguration to add a ProviderSignInController.
Also fix default UserIdSource.

Fixes gh-1050
Merge pull request #1050 from habuma/master

* pull1050:
  Add ProviderSignInController for Spring Social
Fix Devc->Devic

(Leaving the docs changes for later)

Fixes gh-1049
Adjust order of property sources

@PropertySources *can* and should be added in the slot
after the application.properties (code that is part of the
application should have lower precedence than external
configuration).

Fixes gh-1044
Add test for mixed Mongo/Jpa repositories