improvements to Groovy and Scala user guide chapters

- better explain how groovyClasspath and scalaClasspath are inferred

A little more content for the release notes.

Move log warnings about ignored ivy file content down to debug level.

- Ideally, these should only be logged once when the module is actually resolved from a remote repository.
- Once we don't use ivy.xml for internal meta-data persistence, we should be able to move these messages up to WARN, I think.
- Also, used the correct string substitution characters for log messages

Move log warnings about ignored ivy file content down to debug level.

- Ideally, these should only be logged once when the module is actually resolved from a remote repository.
- Once we don't use ivy.xml for internal meta-data persistence, we should be able to move these messages up to WARN, I think.
- Also, used the correct string substitution characters for log messages

Cleaned up the section on dependency resolution tweaking in the User …

…Guide

Changed order and added some minor updates/fixes.

GRADLE-2650: always set http.keepAlive = "true" to work around bugs i…

…n HttpClient-4.2.2

GRADLE-2650: always set http.keepAlive = "true" to work around bugs i…

…n HttpClient-4.2.2

GRADLE-2641 - Some hackery to handle parent POMs with SNAPSHOT versio…

…n. Needs a deeper reworking of parsing to fix properly.

Bumped to use the very latest release snapshot for building