v261
tree-wide: Introduce sd-forward.h and shared-forward.h headers
tree-wide: include unistd.h where necessary
libudev: Clean up includes
tree-wide: normalize comment style
libudev: Don't pull in libshared_static
libudev: Fix declaration argument names
meson: drop libdl, threads, and librt dependencies
license: LGPL-2.1+ -> LGPL-2.1-or-later
tree-wide: standardize header names across src/fundamental, src/basic and src/shared
options: get rid of "on_error" parameter to FOREACH_OPTION