print field names on struct members.

also don't concatenate strings next
to each other in the struct,
like p.doprint does.

expose additional print flags to formatters

R=r
DELTA=128  (111 added, 11 deleted, 6 changed)
OCL=20991
CL=21018

src/lib/fmt/format.go

@@ -50,7 +50,9 @@ export type Fmt struct {
 }
 
 func (f *Fmt) clearflags() {
+	f.wid = 0;
 	f.wid_present = false;
+	f.prec = 0;
 	f.prec_present = false;
 	f.minus = false;
 	f.plus = false;