Update 1-05-changes.rst

Updated changelog to use tables to outline changes, etc
Documentation section needs more work/thought
In relation to: https://github.com/IATI/IATI-Guidance/commit/8fb6fb18d05f779b356457857dc5d73aa6a65b42#diff-0ebfb6d2aae9c405a9aa3203cff94affR23