Also, rearrange and clean up some things to make this work.
The textarea starts as a single line, but auto-expands when entering
multiple lines (e.g. via Shift+Enter). Pressing just "Enter" still
executes the expression.
Main changes:
- Switched to using `go-bindata` in place of `scripts/embed-static.sh`.
- Support for building Prometheus without a `Makefile`.
- Minor typo fix to make Prometheus build on Windows (without Makefiles).
Please note that this does not mean that prometheus will work on Windows.
There are still failing tests!
