Allow to directly open .tar.lzo files
Steps to reproduce:
- Have a .tar.lzo file
- Try to get a file from within the .tar archive
What happens: The user needs to extract the .tar file first (with the issues in #29). Only then he is able to open the .tar file.
What should happen: File-roller should decompress the whole archive and parse it directly, only saving the index to RAM (and maybe a mapping of compressed to decompressed blocks). Then the user is able to browse the archive. When he wants to extract a single file, file-roller does not need to read the whole file again but knows where to find the file within the compressed archive.