Rewrite with mupdf as a backend (#50)

* Initial implementation of attempted mupdf rewrite

* Change back to no resizing and don't include alpha channel in conversion

* Remove some more dead code

* Make features more modular and call search more easily

* Switch to git dependency for my fixes

* Update deps

* Fix searching hehe

* Remove unnecessary CI steps?

* fontconfig in CI

* perftools in ci

* Final adjustments to conform to mupdf changes

src/tui.rs

@@ -569,8 +569,8 @@ impl Tui {
 	pub fn show_error(&mut self, err: RenderError) {
 		self.set_msg(MessageSetting::Some(BottomMessage::Error(match err {
 			RenderError::Notify(e) => format!("Auto-reload failed: {e}"),
-			RenderError::Doc(e) => format!("Couldn't open document: {e}"),
-			RenderError::Render(e) => format!("Couldn't render page: {e}")
+			RenderError::Doc(e) => format!("Couldn't process document: {e}"),
+			RenderError::Converting(e) => format!("Couldn't convert page after rendering: {e}")
 		})));
 	}