use cobra to build self command line tool

Usage

go get -u github.com/ForgetAll/xcli

uuid:

• xcli uuid: generate uuid
• xcli uuid -t/--trim: generate uuid without '-' char

rand:

• xcli rand: generate a rand number, from 0 to 1<<63 - 1
• xcli rand --from/-f valueFrom --to/-t valueTo: generate a rand in [from, to)
• xcli rand --real/-r: use crypto/rand instead of math/rand to generate random nunber

Contribution

Welcome to discuss or commit pull request!

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