Support autobuild of enhanced reflash records

[anwu]

To improve the upgrade and release process of new firmware, we need to implement a way to automatically build an all firmware inclusive OTA TRUB script. As of now, the autobuild_trub_script only handles basic reflashing of the controller and slot tiles. We want to extend the capability of this function so that it can choose to use an enhanced reflash record as well.

For example, we have

autobuild_trub_script("os_2059_v1_0_ota.trub",
                      [
                          ("controller", "connrf52832_nrf52832_head.elf"),
                          ("slot 1", "firm_gpiopipe_lpc824_hw2.elf")
                      ],
                      (2059, "1.0"))

But we want to be able to update the SoftDevice, as well as executive as well now.
So we need something like

autobuild_trub_script("os_2059_v1_2_ota.trub",
                      [
                          ("controller", "pingpong_exec_bundle"),
                          ("controller", "connrf52832_nrf52832_head.elf", enhanced=True, flags=1),
                          ("controller", "s112_nrf52_6.1.1_softdevice.hex", enhanced=True, flags=0),
                          ("slot 1", "firm_gpiopipe_lpc824_hw2.elf")
                      ],
                      (2059, "1.2"))

This can be done by updating coretools/iotilecore/iotile/core/hw/update/records with a new type of record. And also by updating autobuild_trub_script and its underlying functions to handle the new enhanced reflash record.