Merge branch 'develop' of bitbucket.org:k1jt/wsjtx into develop
QMAP is OK in Linux and macOS. Update Release Notes accordingly.
Minor edits to User Guide, in the Windows Installation section.
Minor editing of top section of Release Notes.
Fix several typos and spellings in the User Guide.
Updates to the User Guide for v2.7.0 GA release.
Merge branch 'develop' of bitbucket.org:k1jt/wsjtx into develop
Minor edits to Release Notes.