Force flag

[JoshVanL]

What this PR does / why we need it:
With the inclusion of more validation and verification checks, the user should have the option to skip these checks. This is implemented with a force flag.

fixes #316

Addition of force flag for cluster sub-command

[JoshVanL]

/assign @simonswine

[JoshVanL]

/unassign

[jetstack-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[jetstack-bot]

@JoshVanL: PR needs rebase.

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[jetstack-bot]

@JoshVanL: The following test failed, say /retest to rerun them all:

Test name	Commit	Details	Rerun command
tarmak-puppet-module-tarmak-acceptance-1-14-centos	6d96c4c	link	/test puppet-tarmak-acceptance-centos v1.14

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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