Added support for StaveText and adding text to StaveConnector.

![2014-03-09 00 24 12](https://f.cloud.github.com/assets/2025065/2365664/bccdacb2-a6d5-11e3-8540-1dd6f03c8b3e.png)
![2014-03-09 00 17 47](https://f.cloud.github.com/assets/2025065/2365657/3533eb72-a6d5-11e3-8dc4-72fd8a2aca0b.png)

+ Added node_modules to gitignore.

+ Added support for StaveText
LeftText can be used for part name.

+ Added support for adding text to StaveConnector
It is also for part name, made it has same x margin with left StaveText.