Add a very basic logger for arethusa

This duplicates the console.log behaviour. We will still use this for
debugging purposes, but for logs we want others to see too we will use
the arethusaLogger. Jshint won't complain then - and we can still let
it track any forgotten console log statements.
Minor fixes in .jshintrc
Add arethusaLogger to jshintrc
Remove jshint arethusaUtil global declarations

We define it in our .jshintrc now.
Fix jshintrc

We cannot set the arethusa variables to read-only as we need to define
them for the first time at some point...
Merge pull request #59 from latin-language-toolkit/arethusa_logger

Arethusa logger
Add grunt-cli to package.json
Defer loading of plugins until state is loaded
Let arethusaUtil.xml2json read from strings
Load treebank data through $http
Make state retrievers factories
Add some more global functions to jshintrc
Add watch task for e2e tests
Add searchbox at top and encode query in url
Add global afterEach to jshintrc
Spec for search controller
Start e2e test for displaying conten from xml
Minimal design change
Remove unwanted rebase remnants
Lazy init of plugins

Starts with #54