Allow to use a configured WebDriver when running with test browser.

Helpers.running and WithBrowser so far only accepted a WebDriver class
to instantiate the appropriate WebDriver.

This change allows to provide an already configured WebDriver instance.
This makes it possible to e.g. create an HtmlUnitDriver for a specific
browser version, like this:

    import org.openqa.selenium.htmlunit._
    import com.gargoylesoftware.htmlunit._
    val driver = new HtmlUnitDriver(BrowserVersion.FIREFOX_17)
    driver.setJavascriptEnabled(true)

    running(TestServer(3333), driver) { browser =>
      ..
    }

For the java version of WithBrowser it seems to be intended that for futher
customization of the browser `WithBrowser#provideBrowser` should be used:
There was no webDriver configuration possible, thus nothing is changed here.

Actually for me using the BrowserVersion.FIREFOX_17 fixed an issue
with jquery: integration tests failed with

    WebDriverException: com.gargoylesoftware.htmlunit.ScriptException: TypeError: Cannot find
    function addEventListener in object [object HTMLDocument]. (http://code.jquery.com/jquery-1.10.1.min.js#5)
Merge pull request #1962 from magro/running-with-webdriver

Allow to use a configured WebDriver when running with test browser
Typo fixes & ToC fix for Scala guide

Typo fixes in ScalaTemplates.md, ScalaCustomTemplateFormat.md
ToC missing a link between 3.2 Common use Cases to custom format in ScalaHome.md
Don’t escape message content in EventSource #1862
A fix in the spirit of PR https://github.com/playframework/playframework/pull/1962, but fixes up a compilation issue that broke the build. The major difference with the API is that instead of passing in a WebDriver class, WebDriver instances are always required. However the default WebDriver instance is of clazz HTMLUNIT. Alternate ones can be passed in using WebDriverFactory(clazz) instead of just clazz as before.
Quick fix for a CI issue in relation to https://github.com/playframework/playframework/pull/1962
Merge pull request #1984 from julienrf/fix/1862

Don’t escape message content in EventSource #1862
Merge pull request #1982 from plepropre/toc_custom_template

Toc custom template : fixing spaces
Merge remote-tracking branch 'origin/master' into actions
Composed ActionBuilders should inherit parser and action modifiers

Also remove inconsistent compose operator from ActionFunction.
Continuing proposal for issue #1986.