__This is a breaking change, but the header and example did warn
everyone that this API was in flux due to the incompatible SD and SPIFFS
File implementations.__
BearSSL CertStores now simply need a filesystem and the names of the
data (generated on-chip) and archive (uploaded by user) files on it.
No more need to roll your own virtual CertStoreFile class.
Update the library, examples, and device test.
Make HTTPClient take a WiFiClient parameter, allowing you to pass in a
simple HTTP WiFiClient or a BearSSL or axTLS WiFiClientSecure with
any desired verification options. Deprecate the older, TLSTraits methods.
Add basic HttpsClient example.
Add optional LED feedback to the Update class