QT_NO_KEYWORDS prevents Qt from defining the `foreach`, `signals`,
`slots` and `emit` macros.
Avoid overlap between Qt macros and boost - for example #undef hackiness
in #6421.
Conflicts:
src/qt/addressbookpage.cpp
src/qt/peertablemodel.cpp
src/qt/receivecoinsdialog.cpp
src/qt/rpcconsole.cpp
Rebased-From: d29ec6c2301e593d577126d1ca85b93307b32bf1
Github-Pull: #6433