Implements #reverse! in Literal::Array (#298)

Addresses #193

Author: hslzr

lib/literal/array.rb

@@ -499,6 +499,11 @@ def reverse(...)
 
 	alias_method :initialize_copy, :replace
 
+	def reverse!
+		@__value__.reverse!
+		self
+	end
+
 	def rotate(...)
 		__with__(@__value__.rotate(...))
 	end

test/array.test.rb

@@ -768,6 +768,14 @@
 	assert_equal return_value, Literal::Array(Integer).new(2, 3, 1)
 end
 
+test "#reverse! reverses the array in place" do
+	array = Literal::Array(Integer).new(1, 2, 3)
+
+	return_value = array.reverse!
+
+	assert_same return_value, array
+end
+
 test "#take takes the first n elements" do
 	array = Literal::Array(Integer).new(1, 2, 3, 4, 5)