Additional callback before file is unzipped.

[mpbachmann]

No description provided.

[jhudsonWA]

@christianbachmann I know this is from way back, but can you comment on the benefit of this new callback :

- (void)zipArchiveWillUnzipFileAtIndex:(NSInteger)fileIndex totalFiles:(NSInteger)totalFiles archivePath:(NSString *)archivePath unzippedFilePath:(NSString *)unzippedFilePath;

vs just using

- (void)zipArchiveWillUnzipFileAtIndex:(NSInteger)fileIndex totalFiles:(NSInteger)totalFiles archivePath:(NSString *)archivePath fileInfo:(unz_file_info)fileInfo;