Staticanalysis: Scalastyle

Changes
-----------
* embed scalastyle configuration files
* at build time extract config files to target directory
* wrap scalastyle InputKey as TaskKey
* projects using this plugin inherit:
  * Test depends on scalastyle-test
  * Package depends on scalastyle-main
* sbt-meow temporarily included for debugging

Check that the appropriate plugins are loaded
----------------------------------------------------------
1. ```sbt hello```
1. ```sbt meow```
1. ```sbt plugins```

To exercise functionality
------------------------------
1. checkout **socrata-sbt-plugins** with this pull request
1. ```sbt clean compile test package publish-local```
  1. test should receive no scalastyle warnings.
  1. package should receive no scalastyle errors.
1. checkout **socrata-sbt-plugins-test-project**
1. ```sbt clean compile test package```
  1. test should receive a warning from scalastyle and proceed.
  1. package should receive an error from scalastyle and halt.

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