README.rst: Update link for cib usage instruction

[ashwani99]

Fixes #1157

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[Adrianzatreanu]

ack 2c5d4b2

[Mixih]

@rultor merge

[rultor]

@rultor merge

@Mixih OK, I'll try to merge now. You can check the progress of the merge here

[rultor]

@rultor merge

@Mixih Done! FYI, the full log is here (took me 1min)