Adjustable paragraph height

Currently, all %table output mode (table, barchart, linechart, piechart ...) height is fixed by 300px.
This PR introduce adjustable table height. It provides small handle on bottom right corner to adjust height.

Here's screenshots of examples.

![image](https://cloud.githubusercontent.com/assets/1540981/5056482/b0f645e2-6cc9-11e4-9346-50ab0ddb4ac8.png)