changed format_item::truncate_ 's type from int to streamsize. that's what it was supposed to be from the start. spotted on 64 bit plaform by A.Leeming

[SVN r22550]

libs/format

@@ -1 +1 @@
-Subproject commit 42532c29426d6252a67d8a62f1df8f1b38dac5d1
+Subproject commit d09013ce9c1de1e291e6e5549e375773556305e3