Pressing tab on a selection indents the selection

See #203

cmd/micro/actions.go

@@ -309,6 +309,16 @@ func (v *View) Delete() bool {
 func (v *View) InsertTab() bool {
 	// Insert a tab
 	if v.Cursor.HasSelection() {
+		if v.Cursor.CurSelection[0].Y != v.Cursor.CurSelection[1].Y {
+			for i := v.Cursor.CurSelection[0].Y; i <= v.Cursor.CurSelection[1].Y; i++ {
+				if settings["tabstospaces"].(bool) {
+					v.Buf.Insert(Loc{0, i}, Spaces(int(settings["tabsize"].(float64))))
+				} else {
+					v.Buf.Insert(Loc{0, i}, "\t")
+				}
+			}
+			return true
+		}
 		v.Cursor.DeleteSelection()
 		v.Cursor.ResetSelection()
 	}

cmd/micro/cursor.go

@@ -293,7 +293,6 @@ func (c *Cursor) Start() {
 func (c *Cursor) GetCharPosInLine(lineNum, visualPos int) int {
 	// Get the tab size
 	tabSize := int(settings["tabsize"].(float64))
-	// This is the visual line -- every \t replaced with the correct number of spaces
 	visualLineLen := StringWidth(c.buf.Line(lineNum))
 	if visualPos > visualLineLen {
 		visualPos = visualLineLen