font.go
func NewSyncFolderFontCache(folder string) *SyncFolderFontCache {
	return &SyncFolderFontCache{
		fonts:  make(map[string]*truetype.Font),
		folder: folder,
		namer:  FontFileName,
	}
}
func NewSyncFolderFontCache(folder string) *SyncFolderFontCache {
	return &SyncFolderFontCache{
		fonts:  make(map[string]*truetype.Font),
		folder: folder,
		namer:  FontFileName,
	}
}
// NewSyncFolderFontCache creates SyncFolderFontCache