stop using any nightly features (ill miss u const traits)

src/utilities/is_overlapping.rs

@@ -0,0 +1,11 @@
+use std::ops::RangeInclusive;
+
+pub trait IsOverlapping {
+	fn is_overlapping(&self, other: &Self) -> bool;
+}
+
+impl IsOverlapping for RangeInclusive<usize> {
+	fn is_overlapping(&self, other: &Self) -> bool {
+		self.contains(other.start()) || self.contains(other.end())
+	}
+}