jsgui: Replace _.template with custom function that strips comments

Makes the source much more readable. Before:
![screen shot 2014-09-26 at 18 48 39](https://cloud.githubusercontent.com/assets/837527/4425034/67da2018-45a5-11e4-8041-43486b1ea6b3.png)
After:
![screen shot 2014-09-26 at 18 45 43](https://cloud.githubusercontent.com/assets/837527/4425006/07877b70-45a5-11e4-9aca-54c0c1340964.png)

The rendered page itself still contains the Apache license header at the top.

Do we want to replace `_.template` or add an alternate function for use with templates likely to contain a license header? I figured the former saves having to replace lots of function calls and will automatically include all templates added in the future.
Doesn't catch windows new line after the comment. This one should work:
/<!--(.|[\n\r\t])*?-->\r?\n?/g