[PATCH] Add #include <limits.h> so that git compiles under Solaris

<JC> Editorial Note.  We may want to include standard headers in one
of those headers everybody includes, e.g. cache.h, to reduce clutters,
but this commit is as Thomas posted to the GIT list.

Date:	Sat, 7 May 2005 10:41:41 +0200
Signed-off-by: Thomas Glanzmann <sithglan@stud.uni-erlangen.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>