container:start stopped working in Scalatra sbt project : "invalid key" - scala

Question

I have a scalatra project built the standard way using giter8.
I am uncertain why container:start no longer functions in my scalatra project: no change was made to build.sbt. here is the error:
Using /home/stephen/.sbt/0.12.0 as sbt dir, -sbt-dir to override.
[info] Set current project to wfdemo (in build file:/home/stephen/wfdemo/)
> container:start
[error] Not a valid key: start (similar: state, startYear, target)
[error] container:start
[error]
Here is the sbt:
object KeywordsservletBuild extends Build {
val Organization = "com.astralync"
val Name = "KeywordsServlet"
val Version = "0.1.0-SNAPSHOT"
val ScalaVersion = "2.11.7"
val ScalatraVersion = "2.4.0-RC2-2"
lazy val project = Project (
"keywordsservlet",
file("."),
settings = ScalatraPlugin.scalatraSettings ++ scalateSettings ++ Seq(
organization := Organization,
name := Name,
version := Version,
scalaVersion := ScalaVersion,
resolvers += Classpaths.typesafeReleases,
resolvers += "Scalaz Bintray Repo" at "http://dl.bintray.com/scalaz/releases",
libraryDependencies ++= Seq(
"org.apache.spark" %% "spark-core" % "1.3.1",
"org.scalatra" %% "scalatra" % ScalatraVersion,
"org.scalatra" %% "scalatra-scalate" % ScalatraVersion,
"org.scalatra" %% "scalatra-specs2" % ScalatraVersion % "test",
"ch.qos.logback" % "logback-classic" % "1.1.2" % "runtime",
"org.eclipse.jetty" % "jetty-webapp" % "9.2.13.v20150730" % "container",
"javax.servlet" % "javax.servlet-api" % "3.1.0" % "provided",
"net.databinder" % "unfiltered-netty_2.11" % "0.8.4"
),
scalateTemplateConfig in Compile <<= (sourceDirectory in Compile){ base =>
Seq(
TemplateConfig(
base / "webapp" / "WEB-INF" / "templates",
Seq.empty, /* default imports should be added here */
Seq(
Binding("context", "_root_.org.scalatra.scalate.ScalatraRenderContext", importMembers = true, isImplicit = true)
), /* add extra bindings here */
Some("templates")
)
)
}
)
)
}
Suggestions appreciated.

Answer 1

Small but not necessarily obvious fix for this:
; container:start ; shell
The leading semicolon is required.