Add '-' and '_' to the 28px font (seem to have got lost during upscale)

Author: gfwilliams

libs/graphics/font/renaissance_crop_28.pbff

@@ -250,7 +250,9 @@ glyph 44 ,
 ##
 -
 glyph 45 -
------------ 0
+----------- 12
+  ########
+  ########
 -
 glyph 46 .
 ----- 18
@@ -1434,7 +1436,9 @@ glyph 94 ^
   ##      ##
 -
 glyph 95 _
---------------- 0
+----------- 20
+  ########
+  ########
 -
 glyph 96 `
 --------- 0
@@ -2390,6 +2394,8 @@ glyph 174 ®
 -
 glyph 175 ¯
 ------------- 0
+  ##########
+  ##########
 -
 glyph 176 °
 ------------- 0
@@ -8175,10 +8181,14 @@ glyph 960 π
     ##      ##
 -
 glyph 8211 –
-------------------- 0
+--------------- 12
+  ############
+  ############
 -
 glyph 8212 —
---------------------------- 0
+----------------- 12
+  ##############
+  ##############
 -
 glyph 8216 ‘
 ------- 0
@@ -8554,7 +8564,9 @@ glyph 8721 ∑
   ##########
 -
 glyph 8722 −
------------ 0
+----------- 12
+############
+############
 -
 glyph 8730 √
 ----------------------- 0