Added support for StaveText

![2014-03-08 22 20 14](https://f.cloud.github.com/assets/2025065/2365416/991f9dc2-a6c4-11e3-9a61-be8ef538fe73.png)

+ Added support for StaveText.
LeftText can be used for labelling instrument name for stave.

+ added node_modules to gitignore.