Add DeleteLine binding

Ref #135

cmd/micro/bindings.go

@@ -54,6 +54,7 @@ var bindingActions = map[string]func(*View) bool{
 	"Cut":                 (*View).Cut,
 	"CutLine":             (*View).CutLine,
 	"DuplicateLine":       (*View).DuplicateLine,
+	"DeleteLine":          (*View).DeleteLine,
 	"Paste":               (*View).Paste,
 	"SelectAll":           (*View).SelectAll,
 	"OpenFile":            (*View).OpenFile,
@@ -859,6 +860,18 @@ func (v *View) DuplicateLine() bool {
 	return true
 }
 
+// DeleteLine deletes the current line
+func (v *View) DeleteLine() bool {
+	v.Cursor.SelectLine()
+	if !v.Cursor.HasSelection() {
+		return false
+	}
+	v.Cursor.DeleteSelection()
+	v.Cursor.ResetSelection()
+	messenger.Message("Deleted line")
+	return true
+}
+
 // Paste whatever is in the system clipboard into the buffer
 // Delete and paste if the user has a selection
 func (v *View) Paste() bool {