Allow runtime selection of render quality hint

This change allows to pass render quality hint to SDL in runtime. While
using hardware display, SDL can hint the renderer to use linear or
anisotropic filtering, which can deliver a better experience when using
non-integer scale value.

data/language/english_uk.txt

@@ -4030,6 +4030,13 @@ STR_5724    :Thunderstorm
 STR_5725    :{BLACK}Force weather:
 STR_5726    :{SMALLFONT}{BLACK}Sets the current weather in park
 
+STR_5727    :Scaling quality
+STR_5728    :Requires hardware display option
+STR_5729    :{SMALLFONT}{BLACK}Requires hardware display option
+STR_5730    :Nearest neighbour
+STR_5731    :Linear
+STR_5732    :Anisotropic
+
 #############
 # Scenarios #
 ################