test with go 1.24 & 1.25

test with go 1.23

test with go 1.22

test with go 1.21

Bump golang.org/x/net from 0.2.0 to 0.7.0

test with go 1.20

fix lint

replace travis with github workflow

upgrade dependencies for go v1.18

upgrade dependencies for go v1.17

upgrade dependencies for go v1.16

Fix unit tests

Test go1.13 in ci

update readme

use go module for go version >= 1.11