New function addFileListRecord()

This function takes care about appending of FileListRec structure
to the FileList struct's files.
Split handlePreambleTag() into handlePreambleTag() and applyPreambleTag()
MFS - Initial commit
Propagate spec further in build/files.c
addFileListRecord() moved to build/files_internal.h
MFS do not ignore glob in filehooks
mfs: fix adding of summary in mfsPackageNew()