patterns/uf2: Added Family ID enum to uf2.hexpat, Added missing description pragmas and other minor fixes (#282)

* patterns/uf2: add family ID enum

* patterns/uf2: Fix enum spacing

* patterns: add missing description pragmas and README entries, etc.

* patterns/uf2: add reference for Family ID enum

patterns/xgspak.hexpat

@@ -1,3 +1,6 @@
+#pragma author LolHacksRule
+#pragma description Exient XGS Engine Pak files
+
 import std.mem;
 import std.core;
 import type.time;