Move classes into separate files

FossilOrigin-Name: 14861826d4c1f561aca909afe773366a46b57b20cf41fd668092dfb98d960d80

src/MapModelInfo.m

@@ -0,0 +1,20 @@
+#import "MapModelInfo.h"
+
+@implementation MapModelInfo
+- (instancetype)initWithRad:(int)rad
+                          h:(int)h
+                       zoff:(int)zoff
+                       snap:(int)snap
+                       name:(OFString *)name
+{
+	self = [super init];
+
+	_rad = rad;
+	_h = h;
+	_zoff = zoff;
+	_snap = snap;
+	_name = [name copy];
+
+	return self;
+}
+@end