Add description to theme crate.
+/*!
+
+This crate provides functions to load a css files as theme and access it properties with
+selectors.
+
+This crate depends on the orbtk_utils crate.
+
+# Example
+
+Basic usage of the tree:
+
+```rust,no_run
+
+use orbtk_css_engine::prelude::*;
+
+let mut theme = Theme::create_from_path("theme.css").build();
+let selector = Selector::from("button");
+let background = theme.brush("background", &selector);
+
+```
+
+ */
pub use selector::*;
pub use theme::*;
