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
added some examples for the Accept-Encoding header
Don’t escape message content in EventSource #1862
moved accept header parsing to a slightly better place
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.
detect whether gzip is an accepted and preferred content encoding
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
Upgraded to SBT 0.13

* Actually upgraded to 0.13.1-RC2 to address
  https://github.com/sbt/sbt/issues/937
* Also had to upgrade to specs 2.3.1 to work around issue with scalaz
  pulling in Scala 2.10.1 and SBT not honouring our scala version
* Upgraded scalariform, which meant some files change formatting
* SBT runs forked tests in a different directory, changed the tests that
  failed as a result to hopefully be more resilient to working directory
  changes
* Implements #1643
* Also fixed #1710 - caching is now used for scala/javadoc compilation
Added a test for anorm
Merge pull request #1982 from plepropre/toc_custom_template

Toc custom template : fixing spaces
changed things as requested by pull request review
Add note about scalariform to contributor guidelines
quickfix for return type of the SimpleResult methods
[#826] Make Promise.{flat,}map allow supertypes
Merge pull request #1989 from asflierl/1983_correctly_handle_accept_encoding_gzip

correctly handle accept encoding gzip
Merge pull request #1992 from jroper/anorm-tests

Added a test for anorm
Merge pull request #1998 from baloo/improvements/826-Promise.flatMap

[#826] Make Promise.{flat,}map allow supertypes