Restructure project directories (#333)

`/client/web` -> `/frontend`
`/client/cli` -> *delete for now*
`/client/native` -> *delete for now*
`/core/editor` -> `/editor`
`/core/document` -> `/graphene`
`/core/renderer` -> `/charcoal`
`/core/proc-macro` -> `/proc-macros` *(now plural)*

editor/src/misc/macros.rs

@@ -0,0 +1,138 @@
+/// Counts args in the macro invocation by adding `+ 1` for every arg.
+///
+/// # Example
+///
+/// ```ignore
+/// let x = count_args!(("example1"), (10), (25));
+/// assert_eq!(x, 3);
+/// ```
+/// expands to
+/// ```ignore
+/// let x = 0 + 1 + 1 + 1;
+/// assert_eq!(x, 3);
+/// ```
+macro_rules! count_args {
+	(@one $($t:tt)*) => { 1 };
+	($(($($x:tt)*)),*$(,)?) => {
+		0 $(+ count_args!(@one $($x)*))*
+	};
+}
+
+/// Generates a [`std::collections::HashMap`] for `ToolState`'s `tools` variable.
+///
+/// # Example
+///
+/// ```ignore
+/// let tools = gen_tools_hash_map! {
+/// 	Select => select::Select,
+/// 	Crop => crop::Crop,
+/// };
+/// ```
+/// expands to
+/// ```ignore
+/// let tools = {
+/// 	let mut hash_map: std::collections::HashMap<crate::tool::ToolType, Box<dyn crate::tool::Tool>> = std::collections::HashMap::with_capacity(count_args!(/* Macro args */));
+///
+/// 	hash_map.insert(crate::tool::ToolType::Select, Box::new(select::Select::default()));
+/// 	hash_map.insert(crate::tool::ToolType::Crop, Box::new(crop::Crop::default()));
+///
+/// 	hash_map
+/// };
+/// ```
+macro_rules! gen_tools_hash_map {
+	($($enum_variant:ident => $struct_path:ty),* $(,)?) => {{
+		let mut hash_map: ::std::collections::HashMap<$crate::tool::ToolType, ::std::boxed::Box<dyn for<'a> $crate::message_prelude::MessageHandler<$crate::tool::tool_messages::ToolMessage,$crate::tool::ToolActionHandlerData<'a>>>> = ::std::collections::HashMap::with_capacity(count_args!($(($enum_variant)),*));
+		$(hash_map.insert($crate::tool::ToolType::$enum_variant, ::std::boxed::Box::new(<$struct_path>::default()));)*
+
+		hash_map
+	}};
+}
+
+/// Creates a string representation of an enum value that exactly matches the given name of each enum variant
+///
+/// # Example
+///
+/// ```ignore
+/// enum E {
+/// 	A(u8),
+/// 	B
+/// }
+///
+/// // this line is important
+/// use E::*;
+///
+/// let a = E::A(7);
+/// let s = match_variant_name!(match (a) { A, B });
+/// ```
+///
+/// expands to
+///
+/// ```ignore
+/// // ...
+///
+/// let s = match a {
+/// 	A { .. } => "A",
+/// 	B { .. } => "B"
+/// };
+/// ```
+macro_rules! match_variant_name {
+	(match ($e:expr) { $($v:ident),* $(,)? }) => {
+		match $e {
+			$(
+				$v { .. } => stringify!($v)
+			),*
+		}
+	};
+}
+
+/// Syntax sugar for initializing an `ActionList`
+///
+/// # Example
+///
+/// ```ignore
+/// actions!(DocumentMessage::Undo, DocumentMessage::Redo);
+/// ```
+///
+/// expands to:
+/// ```ignore
+/// vec![vec![DocumentMessage::Undo, DocumentMessage::Redo]];
+/// ```
+///
+/// and
+/// ```ignore
+/// actions!(DocumentMessage; Undo, Redo);
+/// ```
+///
+/// expands to:
+/// ```ignore
+/// vec![vec![DocumentMessage::Undo, DocumentMessage::Redo]];
+/// ```
+///
+macro_rules! actions {
+	($($v:expr),* $(,)?) => {{
+		 vec![$(vec![$v.into()]),*]
+	}};
+	($name:ident; $($v:ident),* $(,)?) => {{
+		 vec![vec![$(($name::$v).into()),*]]
+	}};
+}
+
+/// Does the same thing as the `actions!` macro but wraps everything in:
+///
+/// ```ignore
+/// fn actions(&self) -> ActionList {
+///		actions!(…)
+/// }
+/// ```
+macro_rules! advertise_actions {
+	($($v:expr),* $(,)?) => {
+		fn actions(&self) -> $crate::communication::ActionList {
+			 actions!($($v),*)
+		}
+	};
+	($name:ident; $($v:ident),* $(,)?) => {
+		fn actions(&self) -> $crate::communication::ActionList {
+			 actions!($name; $($v),*)
+		}
+	}
+}