* Adds transaction_context and instruction_context where invoke_context.get_keyed_accounts() is used.
* Use instruction_context.get_instruction_data() instead of an explicit parameter.
* Removes instruction_data parameter from Executor::execute().
* Removes instruction_data parameter from ProcessInstructionWithContext.
* Use instruction_account_indices, get_sysvar_with_account_check2 and instruction_context.get_signers in vote processor.
* Replaces KeyedAccount by BorrowedAccount in vote processor.
* Removes KeyedAccount from benches in vote processor.
* Unifies SysvarCache filling in the runtime and tests.
Removes new_mock_with_sysvars_and_features()
Removes mock_process_instruction_with_sysvars().
Replaces from_keyed_account() by SysvarCache in vote processor.
* Replaces from_keyed_account() by SysvarCache in BPF loader.
