Make context fonts configurable

Fixes #362

data/text/ghosts.txt

@@ -0,0 +1,42 @@
+Go to sleep my babies
+Don't you wake up
+The stars will keep you company
+So close your eyes
+Old Uncle Moon will shine his dearest sweetest dreams
+And hold you in your arms
+Until the morning comes.
+
+Night Light
+
+Dark the night, not a sound
+Damp and cold, frosty ground
+Above your head the lion screams
+To tear you from your moonlit dreams.
+Damp with sweat, mouth is dry
+Twisted branches catch the eye
+Beside your bed the angel stands
+You cannot touch his withered hands.
+
+Guardian Angel
+
+As the lion's eyes dance before me
+They are kindly yet bloody red
+I can see that he is smiling
+But I cannot live inside his head.
+There the needle stands before me
+I climb inside it towards the light
+Where the angel stands in glory
+His sword of peace defends the night.
+So the world is spread before
+As I fly high on angel wings
+But the angel is deceiving
+For he is weeping as he sings.
+
+Night Light (continued)
+
+Early birds, morning breeze
+Spinning leaves, sleepy trees
+Gently tap the window pane
+It's good to see the sun again.
+
+(Dave Cousins)