[four-in-a-row] Fix typos.

[Arnaud B. <arnaudb src gnome org>]

commit 2a883c10a9df62c4f58439edaa14d7b834c00a19
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Sat Jun 13 21:08:08 2020 +0200

    Fix typos.
    
    Found by [Codespell](https://github.com/codespell-project/codespell).

 data/org.gnome.Four-in-a-row.appdata.xml.in | 2 +-
 src/ai.vala                                 | 2 +-
 src/four-in-a-row.vala                      | 2 +-
 src/game-board-view.vala                    | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/data/org.gnome.Four-in-a-row.appdata.xml.in b/data/org.gnome.Four-in-a-row.appdata.xml.in
index d667818..c0fb8eb 100644
--- a/data/org.gnome.Four-in-a-row.appdata.xml.in
+++ b/data/org.gnome.Four-in-a-row.appdata.xml.in
@@ -65,7 +65,7 @@
   </content_rating>
 
   ​<releases>
-    <!-- should be kept in versionning inverted order -->
+    <!-- should be kept in versioning inverted order -->
   ​  <release version="3.37.2" date="2020-05-30" type="development" urgency="low"/>
     <release version="3.36.3" date="2020-05-30" type="stable" urgency="medium"/>
   </releases>
diff --git a/src/ai.vala b/src/ai.vala
index 49d603e..c6843e5 100644
--- a/src/ai.vala
+++ b/src/ai.vala
@@ -272,7 +272,7 @@ namespace AI
         return true;
     }
 
-    /* makes a move into the column'th column. Returns true if the move was succesful, false if it wasn't */
+    /* makes a move into the column'th column. Returns true if the move was successful, false if it wasn't */
     private static bool move (Player player, uint8 column, ref Player [,] board)
     {
         uint8 n_rows = (uint8) board.length [0];
diff --git a/src/four-in-a-row.vala b/src/four-in-a-row.vala
index dcfd7ce..cd527f0 100644
--- a/src/four-in-a-row.vala
+++ b/src/four-in-a-row.vala
@@ -70,7 +70,7 @@ private class FourInARow : Gtk.Application
     // animation
     private static AnimID anim = AnimID.NONE;
     private uint8 [,] blink_lines = {{}};
-    private uint8 blink_line = 0;   // index of currenly blinking line in blink_lines
+    private uint8 blink_line = 0;   // index of currently blinking line in blink_lines
     private Player blink_t = Player.NOBODY;    // garbage
     private uint8 blink_n = 0;
     private bool blink_on = false;
diff --git a/src/game-board-view.vala b/src/game-board-view.vala
index f16307c..fa8d5ec 100644
--- a/src/game-board-view.vala
+++ b/src/game-board-view.vala
@@ -225,7 +225,7 @@ private class GameBoardView : Gtk.DrawingArea
     /**
      * column_clicked:
      *
-     * emited when a column on the game board is clicked
+     * emitted when a column on the game board is clicked
      *
      * @column:
      *