[DOCS] Clarified that you must remove X-Pack plugin when upgrading#32016

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debadair merged 1 commit intoelastic:masterfrom

debadair:upgrade_clarification

Jul 20, 2018

Commits on Jul 12, 2018

[DOCS] Clarified that you must remove X-Pack plugin when upgrading from pre-6.3.
debadair
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