Merge #9260: Mrs Peacock in The Library with The Candlestick (killed main.{h,cpp})

76faa3c Rename the remaining main.{h,cpp} to validation.{h,cpp} (Matt Corallo)
e736772 Move network-msg-processing code out of main to its own file (Matt Corallo)
87c35f5 Remove orphan state wipe from UnloadBlockIndex. (Matt Corallo)

src/policy/policy.cpp

@@ -7,7 +7,7 @@
 
 #include "policy/policy.h"
 
-#include "main.h"
+#include "validation.h"
 #include "tinyformat.h"
 #include "util.h"
 #include "utilstrencodings.h"