These headers are not entirely private to libnm-core as they are also
used by keyfile plugin. Merge them to a new header file
nm-keyfile-internal.h so that the name makes the internal nature of the
header more apparent.
This is the first step to move keyfile to libnm. For now, only
copy the files to make later changes nicer in git-history.
/bin/cp src/settings/plugins/keyfile/reader.c libnm-core/nm-keyfile-reader.c
/bin/cp src/settings/plugins/keyfile/reader.h libnm-core/nm-keyfile-reader.h
/bin/cp src/settings/plugins/keyfile/utils.c libnm-core/nm-keyfile-utils.c
/bin/cp src/settings/plugins/keyfile/utils.h libnm-core/nm-keyfile-utils.h
/bin/cp src/settings/plugins/keyfile/writer.c libnm-core/nm-keyfile-writer.c
/bin/cp src/settings/plugins/keyfile/writer.h libnm-core/nm-keyfile-writer.h