Test worker pay computation when maintenance interval is not 1 day

[theoreticalbts]

Specifically,

graphene/libraries/chain/db_maint.cpp

Lines 110 to 116 in dffc83c

	if( _pending_block.timestamp - get_dynamic_global_properties().last_budget_time != fc::days(1) )
	{
	fc::uint128 pay(requested_pay.value);
	pay *= (_pending_block.timestamp - get_dynamic_global_properties().last_budget_time).count();
	pay /= fc::days(1).count();
	requested_pay = pay.to_uint64();
	}

should be covered by this test.

[vikramrajkumar]

This issue was moved to bitshares/bitshares-core#52