Reordering quickstart content

[#55151742]
Added example build badges
Show forum icon
Quick Start jump link now works
Gradle and maven snippets can be externalised

* Maven templates go in _includes/maven_{dependency,repository}.xml
* Gradle templates go in _includes/gradle_{dependency,repository}.gradle

Example maven_dependency.xml

    <dependency>
        <groupId>{@= groupId @}</groupId>
        <artifactId>{@= artifactId @}</artifactId>
        <version>{@= version @}</version>
    </dependency>

[#55283992]
Project authors can override dependency snippet rendering

- For example, create _includes/pom.xml with the following content:

    <dependencies>
        <dependency>
            <groupId>{@= groupId @}</groupId>
            <artifactId>{@= artifactId @}</artifactId>
            <version>{@= version @}</version>
        </dependency>
    </dependencies>
    {@ if (repository) { @}
    <repositories>
        <repository>
            <id>{@= repository.id @}</id>
            <name>{@= repository.name @}</name>
            <url>{@= repository.url @}</url>
            <snapshots>
                <enabled>{@= repository.snapshotsEnabled @}</enabled>
            </snapshots>
        </repository>
    </repositories>{@ } @}

- For gradle, create _includes/build.gradle with the following content:
Merge commit '540075dead8c253a4a94ea686ce3b3b71638ba35' into gh-pages

* commit '540075dead8c253a4a94ea686ce3b3b71638ba35':
  Project authors can override dependency snippet rendering
  Gradle and maven snippets can be externalised
  Quick Start jump link now works
  Show forum icon
  Added example build badges
  Reordering quickstart content