Add support for go1.9

[donnol]

gotrace$ gotrace ./trace.out panic: unsupported trace file version 1.9 (update Go toolchain) 1009

goroutine 1 [running]: main.main() /mnt/e/go/src/github.com/divan/gotrace/main.go:35 +0x2c8

[shunmian]

Is it possible to add support for version go 1.11? gotrace ./trace.out ./binary throw panic: not a trace file for go 1.11.

[divan]

There is a go1.11 branch, but it's not ready yet. See my comment here https://github.com/divan/gotrace/issues/20#issuecomment-438646544