Add methods for tiers, tenants and companies (#115)

* Add missing methods

* Simplify exports

* fix type errors

* fix test

* Add changeset and rename method

* Remove public type

Author: mattvagni

.changeset/mighty-moles-raise.md

@@ -0,0 +1,27 @@
+---
+'@team-plain/typescript-sdk': major
+---
+
+Added the following queries:
+- `getCustomerCustomerGroupMemberships`
+- `getCustomerTenantMemberships`
+- `getTenantById`
+- `getTenants`
+- `searchTenants`
+- `getCompanies`
+- `searchCompanies`
+- `getTierById`
+- `getTiers`
+
+
+Added support for the following mutations:
+- `upsertTenant`
+- `setCustomerTenants`
+- `addCustomerToTenants`
+- `removeCustomerFromTenants`
+- `updateCustomerCompany`
+- `addMembersToTier`
+- `removeMembersFromTier`
+
+Breaking change:
+- You previously received customer group memberships whenever you got a customer back. As there might be many customer groups this is now it's own separate query (`getCustomerCustomerGroupMemberships`). This allows you to fetch and paginate through a customer's customer groups.