Build out of the box with sbt-extras

When using sbt-extras, I hit this issue:

````
[info] Resolving org.clapper#avsl_2.9.2;0.3.6 ...
[warn]  module not found: org.clapper#avsl_2.9.2;0.3.6
[warn] ==== local: tried
[warn]   /home/noahlz/.ivy2/local/org.clapper/avsl_2.9.2/0.3.6/ivys/ivy.xml
[warn] ==== java m2: tried
[warn]   http://download.java.net/maven/2/org/clapper/avsl_2.9.2/0.3.6/avsl_2.9.2-0.3.6.pom
[warn] ==== public: tried
[warn]   http://repo1.maven.org/maven2/org/clapper/avsl_2.9.2/0.3.6/avsl_2.9.2-0.3.6.pom
[warn]  ::::::::::::::::::::::::::::::::::::::::::::::
[warn]  ::          UNRESOLVED DEPENDENCIES         ::
[warn]  ::::::::::::::::::::::::::::::::::::::::::::::
[warn]  :: org.clapper#avsl_2.9.2;0.3.6: not found
[warn]  ::::::::::::::::::::::::::::::::::::::::::::::
````

This change allows you to build this g8 template out of the box.