update README.md
add new config module.

- well inline documented.
- have yet test.
fix wrong sytanx in config.ls
refactory gulp.ls

- use new config loader.
- rewrite gulp init.
  - rename gulp.init-gulp to gulp.init.
- add some explains.
- make build:css build things correctly.
make tester works.
remove build from gulp test deps.
remove gulp task:build from  server deps .
test
use gulp-if to trigger less.
add missing.
remov no need css settings in build.config.json.