Add placeholder support to LoggingApplicationListener

When logging.level.* is set in external configuration they can now
contain placeholders.

Fixes gh-1680
Merge branch '1.1.x'
Fix asciidoctor 'spaces' conversion issues
Add `hide-uri-scheme` attribute to docs
Escape `...*...` outputs using `+...*...+`
Polish
Merge branch '1.1.x'

Conflicts:
	spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc
Escape `...*...` outputs using `+...*...+`
Add @since tag
Support Windows UNC paths with fat jars

Update `Launcher` and `JarFile` to correctly deal with Windows UNC
paths.

Fixes gh-1641
Merge branch '1.1.x'
Revert "Add ActiveMQ MQTT connection URL auto-detection"

This reverts commit 0d8bde58c905f3857d92cee7c2c4334b22985b59.

Fixes gh-1679