Suggest more simple method to inverse weight for MST in Graph

[ci skip]

doc/Graph.xml

@@ -184,16 +184,16 @@
 		<method name="minimum_spanning_tree" qualifiers="const">
 			<return type="Array" />
 			<description>
-				Returns a minimum spanning tree (MST) of this graph. The MST is represented as an [Array] of [GraphEdge]s in this graph, from which you can create a new [Graph], if you need to.
+				Returns a minimum spanning tree (MST) of this graph. An MST is represented as an [Array] of [GraphEdge]s in this graph, from which you can create a new [Graph], if you need to.
 				The [member GraphEdge.value] is interpreted as a [float] weight, which is up to you to define.
 				In order to obtain a [i]maximum spanning tree[/i], you can inverse the weights, for example:
 				[codeblock]
 				var a = graph.add_vertex(Vector2(0, 0))
 				var b = graph.add_vertex(Vector2(100, 100))
 				var w = a.value.distance_to(b.value) # Euclidean distance.
-				w = 1.0 / w
-				graph.add_edge(a, b, w)
+				graph.add_edge(a, b, -w) # Notice negative weight.
 				[/codeblock]
+				[b]Note:[b] there may exist several MSTs if some edges have equal weight. If weights are not configured, the method will eliminate all edges that cause cycles (a tree is an acyclic graph).
 			</description>
 		</method>
 		<method name="remove_edge">