Fix parsing of GPL files

Can you tell this was *not* tested whatsoever?

test/gfx/full_gpl.flags

@@ -0,0 +1 @@
+-c gpl:full_gpl.gpl

test/gfx/full_gpl.gpl

@@ -0,0 +1,36 @@
+GIMP Palette
+#Palette Name: AxulArt 32 color Palette
+#Description: 32-color palette, intended to be similar to that used in arcade and Game Boy Advance games; You can see more of my art at: https://axulart.tumblr.com/ and https://axulart.itch.io/
+#Colors: 32
+0 0 0 000000
+252 252 252 fcfcfc
+196 199 238 c4c7ee
+154 143 224 9a8fe0
+99  93  150 635d96
+41  47  101 292f65
+27  29  52  1b1d34
+255 227 174 ffe3ae
+205 187 171 cdbbab
+166 133 143 a6858f
+207 93  139 cf5d8b
+150 73  104 964968
+255 180 130 ffb482
+221 134 125 dd867d
+178 105 111 b2696f
+246 198 94  f6c65e
+228 144 87  e49057
+196 104 51  c46833
+176 208 126 b0d07e
+102 170 93  66aa5d
+82  181 171 52b5ab
+42  131 121 2a8379
+28  86  89  1c5659
+123 225 246 7be1f6
+88  159 252 589ffc
+80  105 228 5069e4
+46  68  174 2e44ae
+128 86  212 8056d4
+90  59  150 5a3b96
+255 186 225 ffbae1
+230 135 197 e687c5
+167 89  185 a759b9