- update documentation and comments

README.md

@@ -94,6 +94,7 @@ type List interface {
 	Sort(comparator utils.Comparator)
 	Swap(index1, index2 int)
 	Insert(index int, values ...interface{})
+	Set(index int, value interface{})
 
 	containers.Container
 	// Empty() bool

lists/doublylinkedlist/doublylinkedlist.go

@@ -293,7 +293,7 @@ func (list *List) Insert(index int, values ...interface{}) {
 	}
 }
 
-// Sets value at specified index position
+// Set value at specified index position
 // Does not do anything if position is negative or bigger than list's size
 // Note: position equal to list's size is valid, i.e. append.
 func (list *List) Set(index int, value interface{}) {

lists/singlylinkedlist/singlylinkedlist.go

@@ -261,7 +261,7 @@ func (list *List) Insert(index int, values ...interface{}) {
 	}
 }
 
-// Sets value at specified index
+// Set value at specified index
 // Does not do anything if position is negative or bigger than list's size
 // Note: position equal to list's size is valid, i.e. append.
 func (list *List) Set(index int, value interface{}) {