Missing:
----------
1) com.google.gwt:gwt-user:jar:1.7

  Try downloading the file manually from the project website.

  Then, install it using the command: 
      mvn install:install-file -DgroupId=com.google.gwt
-DartifactId=gwt-user -Dversion=1.7 -Dpackaging=jar -Dfile=/path/to/file

  Alternatively, if you host your own repository you can deploy the file
there: 
      mvn deploy:deploy-file -DgroupId=com.google.gwt -DartifactId=gwt-user
-Dversion=1.7 -Dpackaging=jar -Dfile=/path/to/file -Durl=[url]
-DrepositoryId=[id]

  Path to dependency: 
          1) com.totsp.gwt:maven-googlewebtoolkit2-sample-rpc:jar:1.0-SNAPSHOT
          2) com.google.gwt:gwt-user:jar:1.7