remove treehouse-format crate and collapse everything into src

src/lib.rs

@@ -0,0 +1,14 @@
+pub mod cli;
+pub mod config;
+pub mod dirs;
+pub mod fun;
+pub mod generate;
+pub mod history;
+pub mod html;
+pub mod import_map;
+pub mod parse;
+pub mod paths;
+pub mod sources;
+pub mod state;
+pub mod tree;
+pub mod vfs;