Merge pull request #378 from vandenoever/remdep

Move signals CursorAdded, CursorRemoved and CursorMoved to ops.Document.
Fix loading of webodf.css in qtjsruntimetest.
If the <link/> element does not load the css, load the webodf.css in a <script/> element.
Also avoid loading webodf.css more than once.
Use reference counting to make sure that the webodf.css is not removed prematurely.
Improve dependencies for the tests.
NodeJS, qtjsruntime and manifest.json-target are top-level targets. Dependencies between top-level targets should be added with add_dependencies().
Always use <script/> to load css.
Using <link/> can cause problems in certain browsers, notably those based on
QtWebKit. By using only <script/> the behavior varies less across different
ways in which WebODF is used.