Add namespace documentation

include/settings.hpp

@@ -6,6 +6,9 @@
 
 
 namespace rack {
+
+
+/** Process-level globals. */
 namespace settings {
 
 

include/simd/vector.hpp

@@ -4,6 +4,9 @@
 
 
 namespace rack {
+
+
+/** Abstraction of byte-aligned values for SIMD CPU acceleration. */
 namespace simd {