Rebrand 'map object' and 'field object' to 'event object'

graphics/event_objects/palettes/field_object_palette_31.pal

@@ -0,0 +1,19 @@
+JASC-PAL
+0100
+16
+115 197 164
+255 213 180
+246 189 148
+222 148 115
+123 65 65
+255 222 74
+213 172 32
+131 98 0
+164 139 238
+106 82 189
+65 57 98
+238 115 65
+172 65 57
+74 49 49
+255 255 255
+0 0 0