Release qiniupkg.com/x v3.0.1

• 添加 travis ci
• 在 go 1.7 - 1.10 中编译通过 (发现 go 1.9 runtime.Caller 行为与其他版本不一致)

Release qiniupkg.com/x/*

qiniupkg.com/x/bufiox
qiniupkg.com/x/bytes
qiniupkg.com/x/cmdline (from github.com/qiniu/osl/cmdline)
qiniupkg.com/x/config (from qbox.us/cc)
qiniupkg.com/x/ctype
qiniupkg.com/x/errors
qiniupkg.com/x/jsonutil
qiniupkg.com/x/log
qiniupkg.com/x/mockhttp
qiniupkg.com/x/reqid
qiniupkg.com/x/rollog
qiniupkg.com/x/rpc
qiniupkg.com/x/ts
qiniupkg.com/x/url
qiniupkg.com/x/xlog

Release github.com/qiniu/*

github.com/qiniu/bits
github.com/qiniu/bufio
github.com/qiniu/bytes
github.com/qiniu/ctype
github.com/qiniu/errors
github.com/qiniu/log
github.com/qiniu/osl
github.com/qiniu/reqid
github.com/qiniu/ts
github.com/qiniu/xlog

Release qbox.us/*

qbox.us/bufio
qbox.us/ds
qbox.us/errors
qbox.us/osl
qbox.us/path
qbox.us/runner