change gulpfile.js:
add task for js files
add watchers to jade, scss, js files
change gulpfile.js:
add task for livereload server and refresh for other tasks
main.jade: add general structure and move to layouts
gulpfile.js: fix require to gulp-jade
create main.jade
main.jade: create basic markup
add mixins.jade, menu mixin
add b-page.scss, create basic style for page
add basic style for header