pager.h: move declarations for pager.c functions from cache.h

Signed-off-by: Elijah Newren <newren@gmail.com>
Acked-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/grep.c

@@ -30,6 +30,7 @@
 #include "object-name.h"
 #include "object-store.h"
 #include "packfile.h"
+#include "pager.h"
 #include "write-or-die.h"
 
 static const char *grep_prefix;