Bootstrap repository class

- Implement BaseRepository class
- Helper for importing repository class
- Barebone cloudfront class to demonstrate how
  to properly subclass BaseRepository

Note that this commit is untested!
Bootstrap repository class

- Implement BaseRepository class
- Helper for importing repository class
- Barebone cloudfront class to demonstrate how
  to properly subclass BaseRepository
- Add repository settings to  site_conf.conf template

Note that this commit is untested!
Merge branch 'devel_cloud_repository' of github.com:pragmagrid/pragma_boot into devel_cloud_repository
Various changes

- Update CloudFront skeleton
- Update use "repodir" instead of "base_dir"
Implements Http repository class

Note that it still need a lot of logging and testing
Implement CloudFront with signed url support
Various changes

- Move repository inside pragma
- A lot of refactoring
- Define files section in vc-in.xml
- Simplify vcdb.json
Implements file processor support

- Add support for "raw", "gzip" and "splitted_gzip"
- Minor refactoring
Various changes

- Add some logging
- Decompress through shell to prevent memory problem
Delete splited_gzip parts after decompresison
Use wget to download file
Various changes

- Implement splited processor
- Fix multiple vc_file bugs in repository modules
FIXED: Splited processor isn't work
Switch back to old-format vcdb.txt
Update main pragma_boot script to use repository class
Update site_conf.conf.template
Update site_conf.conf.template
Make pragma_boot work with CloudFront
Force replace existing file when deflating
FIXED: Forgot to process vc after downloading