Add parent class loader entries if possible

...otherwise you can see cryptic NoClassDefFound errors
because the application class was loaded from the parent
on the file system, but then it doesn't have access to the
child loaders nested jars.
Add git commit id to MANIFEST in boot tools repackager
Ensure env vars are consulted for PATH
Temporary fix for Spring snapshot changes
Small re-org of PropertiesLauncher
Revert "Temporary fix for Spring snapshot changes"

This reverts commit 8a804f61852100f82aa044c21f0ce6cf2d24bf8c.
Extend PropertiesLauncher to load nested archives

PropertiesLauncher can now be used to run an executable jar, and by
default it will pick up nested archives in lib/ (where the Boot
tools puts them). User can provide loader.path (colon-separated)
to change the nested path.

[#58837492] [bs-330] Add tooling for PropertiesLauncher
Standardize on spring.datasource.* for database config

[Fixes #58921238] [bs-333] spring.database.* and
spring.datasource.* used to configure database
Tidy up log message (add space)
Tooling for PropertiesLauncher in JAR archives

To use PropertiesLauncher instead of JarLauncher in an
executable JAR we have provided tooling support. In Maven
(using the starter parent to default some of the settings):

    <plugin>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-maven-plugin</artifactId>
      <configuration>
        <layout>ZIP</layout>
      </configuration>
    </plugin>

in Gradle:

    apply plugin: "spring-boot"
    springBoot {
        layout = 'ZIP'
      }
    }

[Fixes #58837492] [bs-330] Add tooling for PropertiesLauncher
Add profiles to /env
Stop log4j from moaning on startup
Ensure JdbcTemplate and DB initializer still work when user supplies DataSource
Polish
Allow 'java -jar' to work with signed nested jars

Fix RandomAccessJarFile to correctly read certificate information as
jar entries are loaded. This change allows signed nested jars to be
used as JCE providers.
Update brew install instructions to use tap

Issue: gh-86