bug thephpleague#204 Fix typo in command registration for GenerateKey…

…PairCommand (rvanginneken)

This PR was merged into the 0.9-dev branch.

Discussion
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Fix typo in command registration for GenerateKeyPairCommand

The GenerateKeyPairCommand doesn't show up as a command in the console, because of this small typo.

Commits
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cfe08e5 Fix typo in command registration for GenerateKeyPairCommand