The current FreeBSD Build documentation is a little outdated and underwhelming. This PR updates the doc to
be more informative. It also adds new instructions for building the GUI and adding support for descriptor
wallets.
on vasild's recommendation: it is ok to point the user to download db5 which has an active port package
instead of building db4 from the provided script.
Co-authored-by: Vasil Dimov <vd@freebsd.org>
docs: Linked to the 'Building on FreeBSD' section of the Unix guide where it lists BSD specific guides.
Created a FreeBSD build guide (doc/build-freebsd.md).
Added in warning about the version of 'gdb' installed by default.
Removed the FreeBSD build instructions now that they have their own guide (doc/build-freebsd.md).
Updated the sentence to refer to the BSD guides in the 'doc' directory for more specific BSD build instructions.
Minor grammatical fix.
