add drawer state

This was a flexbox alternative to setting a height/min-height on the body and changing it whenever the window resizes or a toggler inside the drawer is clicked etc.

Example HTML:
````html
<body>
<div id="wrapper" data-ur-toggler-component="content" data-ur-id="menu">
  <div id="menu" data-ur-toggler-component="drawer" data-ur-id="menu">
    ...
  </div>
  <div id="page">
    <header data-ur-toggler-component="button" data-ur-id="menu">Menu</header>
    ...
    <div data-ur-toggler-component="button" data-ur-id="menu" id="mask"></div>
  </div>
</div>
</body>
````

Example Sass:
````scss
html {
  overflow-x: hidden; // need this to not break android viewport
}
body {
  overflow: hidden; // need this to not break android viewport
  position: relative;
}

#wrapper {
  display: -webkit-box !important;
  display: -webkit-flex !important;
  display: flex !important;
  width: 150%;
}
#menu, #page {
  @include transition(0.3s);
  width: 0;
}

#menu {
  @include transform(translate3d(-100%, 0, 0));
  -webkit-box-flex: 1;
  -webkit-flex: 1;
  flex: 1;
  position: relative;
  z-index: 1;
  &:not([data-ur-state="enabled"]) {
    height: 0;
  }
}
#page {
  @include transform(translate3d(-50%, 0, 0));
  -webkit-box-flex: 2;
  -webkit-flex: 2;
  flex: 2;
}
[data-ur-state="enabled"] {
  #menu, #page {
    @include transform(translate3d(0, 0, 0));
  }
}

#mask {
  background: rgba(0, 0, 0, 0.3);
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  &:not([data-ur-state="enabled"]) {
    display: none;
  }
}
````