Using ec2 tags for indicating application proccess status
Fixed tagging in userscript; tested
Updated to statika 0.15; added license
Refactoring:
* maven-style publishing;
* restructured ami classes:
  + separated parts of the userscript;
  + made an abstract `AmazonLinuxAMI` class and an instance of it for a particular version of ami;
  + made tags optional;
  + removed (useless) AMI bundle, DummyDistribution and related test;
* changes in the userscript (applicator):
  + updated to sbt 0.13.0;
  + updated to sbt-s3-resolver 0.6.0;
  + removed dependencies on statika and bundle (now only distribution);
  + removed tagging from the applicator;
Wrote short comments for the code
Simplified build definition (using sbt-statika more)
Fixed version of sbt (0.13); set publishBucketSuffix key
Merge branch 'feature/ec2-tags'