Long lines
Long lines
long lines
Fix indentation
Do not open Unix
Always display some debug information when linking & removing files
Typo
Add a newline after the HTTP return code when --verbose
Add package and compiler repository state
Add time from start in log statement (useful to profile)

Also, do not flush after each log statement (this might be slow)
Add OpamFilename.ends_with
Add repo/index.packages and repo/index.compilers file scpecs
On update, also create repo/updated.compilers
WIP

checkpoint commit, which needs to be cleaned-up. The way OPAM is upating has evolved.

Summary:
* correctly hanlde compiler updates (instead of the current hack)
* The protocol for updating backends is simplified (which will improve the port to other backends): no ~/.opam/repo/<backend>/updates file anymore
* we relink only package and compiler descriptions which have changed, this is much faster than before!
* `opam update -j10` works well (only useful if you have lots of pinned packages of remote repositories)

Need to analyse the debug log and test, test, test.
WIP

Simplified backends