Replace nonfree Aller Bold font with Fira Bold

It seems to me that the font used so far for HUD and in-game texts
was Aller Bold, which is proprietary: https://www.fontsquirrel.com/fonts/aller

I've replaced it by Fira Sans, which looks quite similar and is
distributed under the terms of the SIL Open Font License 1.0.

Part of #11.

Also fixes issues with the old BitMapFont being corrupted by recent
Godot - it's safer to just keep the TTF and use DynamicFont.

Note that I'm removing the reference to the ArmWrestler font from
the README. I don't see where it would be in use currently.

README.md

@@ -26,8 +26,8 @@ Unless mentioned otherwise, all art assets (files in ``art/``, ``music/`` and
 
 #### Fonts
 
-* [Arm Wrestler](http://www.dafont.com/armwrestler.font) by AJ Paglia.
-  [Freeware](http://cargocollective.com/ajpaglia/De-Commissioned-Fonts).
+* [Fira Sans Bold](http://mozilla.github.io/Fira) by Mozilla Foundation and Telefonica S.A.
+  [SIL Open Font License 1.1](https://github.com/mozilla/Fira/blob/master/LICENSE).
 * [BPdiet](http://backpacker.gr/fonts/8) by Backpacker.
   [Free but custom permissive EULA](http://backpacker.gr/fonts/8) and
   [Creative Commons Attribution - No Derivative Works 3.0 Unported](http://www.1001freefonts.com/bp_diet.font).

art/fonts/firasans_bold_26.tres

@@ -0,0 +1,9 @@
+[gd_resource type="DynamicFont" load_steps=2 format=2]
+
+[ext_resource path="res://art/fonts/FiraSans-Bold.ttf" type="DynamicFontData" id=1]
+
+[resource]
+
+size = 26
+font_data = ExtResource( 1 )
+

hud/hud.tscn

@@ -2,7 +2,7 @@
 
 [ext_resource path="res://hud/hud.gd" type="Script" id=1]
 [ext_resource path="res://art/life_heart.png" type="Texture" id=2]
-[ext_resource path="res://art/font.font" type="BitmapFont" id=3]
+[ext_resource path="res://art/fonts/firasans_bold_26.tres" type="DynamicFont" id=3]
 [ext_resource path="res://art/chirimoya_big.png" type="Texture" id=4]
 [ext_resource path="res://art/borlas.png" type="Texture" id=5]
 [ext_resource path="res://art/text_sbox.png" type="Texture" id=6]
@@ -234,7 +234,7 @@ margin_bottom = 68.0
 
 [node name="amount" type="Label" parent="fruit_count"]
 margin_left = 141.0
-margin_top = 21.0
+margin_top = 17.0
 margin_right = 203.0
 margin_bottom = 65.0
 size_flags_vertical = 1
@@ -256,7 +256,7 @@ texture = ExtResource( 5 )
 
 [node name="life_amount" type="Label" parent="fruit_count"]
 margin_left = 237.0
-margin_top = 21.0
+margin_top = 17.0
 margin_right = 285.0
 margin_bottom = 65.0
 size_flags_vertical = 0

menu/stage_select.gd

@@ -51,7 +51,7 @@ func add_levels():
 		var level_name = Label.new()
 		level_name.set_align(Label.ALIGN_CENTER)
 		level_name.set_text(level.name)
-		level_name.add_font_override("font", preload("res://art/font.font"))
+		level_name.add_font_override("font", preload("res://art/fonts/firasans_bold_26.tres"))
 		level_vbox.add_child(level_name)
 
 		if !gave_focus: