CRM-21109 only clear caches once on cli script, consolidate code

CRM/ACL/BAO/Cache.php

CRM/Contact/BAO/Contact.php

CRM/Contact/BAO/Contact/Utils.php

CRM/Contact/BAO/GroupContact.php

CRM/Contact/BAO/GroupContactCache.php

CRM/Contact/Form/Merge.php

CRM/Contact/Import/Form/Preview.php

CRM/Contact/Import/Parser/Contact.php

CRM/Core/Config.php

CRM/Dedupe/Merger.php

bin/cli.class.php

tests/phpunit/CRM/Contact/BAO/QueryTest.php

tests/phpunit/api/v3/ContactTest.php

tests/phpunit/api/v3/ReportTemplateTest.php