resolc crate (#328)

- Factor the YUL crate out of `revive-solidity`.
- `revive-solidity` is in reality not a Solidity implementation but the
revive solidity compiler driver (`resolc`). By renaming we not only get
this straight but also a binary with the same name as the crate which
should be less confusing.

---------

Signed-off-by: Cyrill Leutwiler <bigcyrill@hotmail.com>

crates/yul/src/lexer/token/location.rs

@@ -0,0 +1,55 @@
+//! The lexical token location.
+
+use serde::Deserialize;
+use serde::Serialize;
+
+/// The token location in the source code file.
+#[derive(Debug, Serialize, Deserialize, Clone, Copy, Eq)]
+pub struct Location {
+    /// The line number, starting from 1.
+    pub line: u32,
+    /// The column number, starting from 1.
+    pub column: u32,
+}
+
+impl Default for Location {
+    fn default() -> Self {
+        Self { line: 1, column: 1 }
+    }
+}
+
+impl Location {
+    /// Creates a default location.
+    pub fn new(line: u32, column: u32) -> Self {
+        Self { line, column }
+    }
+
+    /// Mutates the location by shifting the original one down by `lines` and
+    /// setting the column to `column`.
+    pub fn shift_down(&mut self, lines: u32, column: u32) {
+        if lines == 0 {
+            self.shift_right(column);
+            return;
+        }
+
+        self.line += lines;
+        self.column = column;
+    }
+
+    /// Mutates the location by shifting the original one rightward by `columns`.
+    pub fn shift_right(&mut self, columns: u32) {
+        self.column += columns;
+    }
+}
+
+impl PartialEq for Location {
+    fn eq(&self, other: &Self) -> bool {
+        self.line == other.line && self.column == other.column
+    }
+}
+
+impl std::fmt::Display for Location {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}:{}", self.line, self.column)
+    }
+}