commit.h: remove method declarations

These methods are now declared in commit-reach.h. Remove them from
commit.h and add new include statements in all files that require these
declarations.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/merge-base.c

@@ -7,6 +7,7 @@
 #include "revision.h"
 #include "parse-options.h"
 #include "repository.h"
+#include "commit-reach.h"
 
 static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
 {