* Move append_vec bench to the crate with append_vec
* Use black_box to tell the compiler not to optimize away test data
```
pub fn black_box<T>(dummy: T) -> T {
unsafe {
let ret = std::ptr::read_volatile(&dummy);
std::mem::forget(dummy);
ret
}
}
```
* Revert "Use black_box to tell the compiler not to optimize away test data"
This reverts commit 5610b8ee95.
* Use black_box to tell the compiler not to optimize away test data
* Create bench directories
The previous code was assuming the instruction index and the
program_id index were the same. That's always true for
single-instruction transactions, but not for multiples.
Added CompiledInstruction::program_id() so that we don't need to pass
around instruction indexes just for Message::program_id().
Also added Message.program_ids() that returns a slice so that we
can move those pubkeys into Message::account_keys.
* Implement finalizer so that all locked accounts are dropped when finalizer goes out of scope
* Add test for tx error with lock conflict
* Fix double unlock from destructor running after a call to unlock
* Add contains_all_parents flag to SlotMeta to prep for tracking detached heads
* Add new DetachedHeads column family
* Remove has_complete_parents
* Fix test
verify_signature() was only used in a test that was testing
binary layout. It only worked because the test transaction only
had one signature.
from() was only used by verify_signature() and that's something
we'd typically called `pubkey()`.
hash() didn't return the hash of the Transaction, as you might
guess. It's only used for PoH, so move it into Entry.
