gnucash maint: Update version in README, add Boost::program_options to dependencies.

[John Ralls]

Updated	 via  https://github.com/Gnucash/gnucash/commit/3d93c7ed (commit)
	from  https://github.com/Gnucash/gnucash/commit/0ca468e0 (commit)



commit 3d93c7edf9b85e6e4185415f805ca0130f0ada75
Author: John Ralls <jralls at ceridwen.us>
Date:   Tue Sep 22 12:35:59 2020 -0700

    Update version in README, add Boost::program_options to dependencies.



Summary of changes:
 README              | 8 +++-----
 README.dependencies | 3 ++-
 2 files changed, 5 insertions(+), 6 deletions(-)