Add possessive apostrophe to "Clients product"

Fix typo from "Clients product" to "Client's product".
Merge pull request #4 from ordonezalex/patch-1

Add possessive apostrophe to "Clients product"
Merge branch 'upstream' into legal

Conflicts:
	development_service_contract.md

Issue https://github.com/danielbeardsley/service_contracts/pull/4 doen't affect
us because there is no missing apostrophe in the new legal clause for 5.1.
Simply stayed with what we have already.