Merge pull request #370 from latin-language-toolkit/refactor_gruntfile_and_templates

Refactor gruntfile and template compilation
Run grunt install in hook if Gruntfile.json changes
Add oc.lazyload
Bundle templates with their modules!
Fx name of history plugin
Remove unnecessary dependency to core

It isn't needed and interferes with our lazy loading.
Remove all plugin script tags from index
Remove all plugin dependencies in arethusa.js
LAZY LOAD MODULES THROUGH PLUGIN CONFIGURATION
React to new plugins syntax in mainCtrl
Start to load external dependencies on the fly
Load dagre and d3 dynamically
Disable the unused config editor for now
Rename arethusa.history template folder
Fix templateUrl paths in arethusa.history
Timeout plugins notification

... so that we arrive in the proper digest cycle.
Make lunr a comments dependency
Make all core modules part of arethusa.min.js
Add grunt-contrib-concat
Concatenate all external dependencies