feat: Create site module

src/lib.rs

@@ -15,3 +15,5 @@
     clippy::shadow_unrelated,
     clippy::must_use_candidate
 )]
+
+pub mod site;

src/site.rs

@@ -0,0 +1,4 @@
+//! Management of on-disk layout of the source of a site
+
+/// Representation of the on-disk structure of a site
+pub struct Site {}