Teams for Woocommerce Memberships 1.7.4

* Fix - Ensure sign up fees are correctly applied when adding new seats to a subscription-based team
* Fix - Do not enable seat changes from customer dashboard for subscription-tied teams if the pricing is per-team based and seats are unlimited
* Fix - If team access is used with a variable subscription product, but switching is disabled, the switch button shouldn't appear to team members
* Fix - Address a potential PHP error on user memberships when a team member could not be determined to gather team details

* Fix - When a team is linked to a subscription product with a limitation, override the limitation if the team owner wants to add a seat, without incurring into product purchase errors
* Fix - Remove a pending invitation when a team owner sends email invitations to new users, once they register and accept the invitation to join
* Fix - Ensure that the "Add Member" button in My Account dashboard template uses the same button styling as WooCommerce
* Misc - Add support for WooCommerce 3.6
* Misc - Require PHP 5.4+

* Fix - Only display the Teams menu item in My Account dashboard page if there is at least one Team the current user can manage
* Fix - Allow removing a member from an existing team linked to an expired subscription to and adding them as members of another team with free seats and non expired status