Botan is a BSD-licensed crypto library for C++. It provides applications
with the ability to use a number of cryptographic algorithms, as well as
SSL/TLS, X.509 certificates and CRLs, PKCS #10 certificate requests, a
filter/pipe message processing system, and a wide variety of other
features.

Botan relies on Python3 for its compilation configuration.

To build TPM support, use `TPM=YES`. This option adds a dependency on
`system/trousers`.
