tester: use eosio/authority rather than tester equivalent

[James-Mart]

struct tester_permission_level_weight, struct tester_wait_weight, and struct tester_authority are in tester.cpp, and therefore not visible to tester users.

These structs should be externally accessible, to make it easier for users to call actions in test-cases to update account permissions, etc.

[James-Mart]

What was the reason for not simply putting them in the eosio namespace in the header?

[tbfleming]

They were temporary until the eosio namespace got versions of those. They can be removed now. See eosio/authority.hpp.