This change helps generalize shutdown code so an interrupt can be
provided to libbitcoinkernel callers. This may also be useful to
eventually de-globalize all of the shutdown code.
Co-authored-by: Russell Yanofsky <russ@yanofsky.org>
Co-authored-by: TheCharlatan <seb.kung@gmail.com>
* Use SECP256K1_CONTEXT_NONE when creating signing context, as
SECP256K1_CONTEXT_SIGN is deprecated and unnecessary.
* Use secp256k1_static_context where applicable.
...instead of explicitly calling init::{Set,Unset}Globals.
Cool thing about this is that in both the testing and bitcoin-chainstate
codepaths, we no longer need to explicitly unset globals. The
kernel::Context goes out of scope and the globals are unset
"automatically".
Also construct kernel::Context outside of AppInitSanityChecks()
