There are certain options which we need to share in multiple binaries,
for example, the signer options. Current options parsing function only
accepts 1 extra option handler, which is inflexible. Extend it to take a
list of extra option handlers.
Currently, to add a new CLI flag, caller must append the flag name to
`extra_long_opts`, then pass an extra option handler which can handle
that option. Define a new dataclass which contains both the CLI flag
name and the code to handle that flag for better composition.
Test: th
Bug: 293313353
Change-Id: I758db66dfd95934f5b2701454d97bfe7d37dc16d
c68c6b9530