Squashed commits:
[50607a9] build dist
[ff0c00b] Allow negative numbers to be passed to parseHeight function test case fix
[3ecc1ca] Allow negative numbers to be passed to parseHeight function test case
[d20f670] Allow negative numbers to be passed to parseHeight function fix
[0816163] Allow negative numbers to be passed to parseHeight function
[aa18c63] rebuild dist
[601b5d5] setGridWidth api documentation udpdate
[c309856] Add a parameter to setGridWidth method to allow not to propagate resizing to widgets.
[ea442d1] drag between grids
[50ce614] jqueryui + requirejs note
[3d8a8e1] drag between grids demo
[446dade] drag from sidebar/between grids
[e31d50e] check if element setup before detach
[67274f8] trash zone is accepting only widgets
This update allows use of bower.json main value in buildtools that rely on
the appropriate files being defined in this main array. It also points to
the unminified, but compiled dist versions as per bower spec:
https://github.com/bower/bower.json-spec#main
* Changes main js file to use unminified version
* Adds the gridstack.css file to the main files array
* Moves compiled CSS into `dist` folder (upstream build process needs update)
* Duplicate `src/gridstack.js` into `dist/gridstack.js` (upstream build process needs update)
* Update demo html to point to `dist` instead of `src`
