e2e-tests: Foster IntelliJ for Scala and build.sbt

As that plugin ([1]) is the mainstream one for sbt in IntelliJ IDEA.

Recommend the latter IDE use for this Scala project. Reformat the
build.sbt file accordingly, to start with. IntelliJ so far has been the
most stable and reproducible development environment for Scala with sbt.

[1] https://plugins.jetbrains.com/plugin/1347-scala

Change-Id: Ib1ca9bc7cac4dca5b7da114ea3f3068a522bccd6

Documentation/dev-e2e-tests.txt

@@ -19,7 +19,10 @@ protocol level.
 Gatling is written in Scala, but the abstraction provided by the Gatling DSL makes the scenarios
 implementation easy even without any Scala knowledge.
 
-Examples of scenarios can be found in the `e2e-tests` directory.
+Examples of scenarios can be found in the `e2e-tests` directory. The files in that directory
+should be formatted using the mainstream
+link:https://plugins.jetbrains.com/plugin/1347-scala[Scala plugin for IntelliJ]. The latter is not
+mandatory but preferred for `sbt` and Scala IDE purposes in this project.
 
 == How to build the tests
 

e2e-tests/load-tests/build.sbt

@@ -4,15 +4,15 @@ enablePlugins(GatlingPlugin)
 
 lazy val gatlingGitExtension = RootProject(uri("git://github.com/GerritForge/gatling-git.git"))
 lazy val root = (project in file("."))
-  .settings(
-    inThisBuild(List(
-      organization := "com.google.gerrit",
-      scalaVersion := "2.12.8",
-      version := "0.1.0-SNAPSHOT"
-    )),
-    name := "gerrit",
-    libraryDependencies ++=
-      gatling ++
-        Seq("io.gatling" % "gatling-core" % "3.1.1" ) ++
-        Seq("io.gatling" % "gatling-app" % "3.1.1" )
-  ) dependsOn(gatlingGitExtension)
+    .settings(
+      inThisBuild(List(
+        organization := "com.google.gerrit",
+        scalaVersion := "2.12.8",
+        version := "0.1.0-SNAPSHOT"
+      )),
+      name := "gerrit",
+      libraryDependencies ++=
+          gatling ++
+              Seq("io.gatling" % "gatling-core" % "3.1.1") ++
+              Seq("io.gatling" % "gatling-app" % "3.1.1")
+    ) dependsOn gatlingGitExtension