Remove the complex and unused `opam config {asm,byte}{comp,link}`
Remove the complex and unused `opam config -I` command
Simplify the libraries and syntax fields

Show them on `opam show`
Simplify the structure of .config file

No more subsections, only a list of variables.
Update the dev manual
Update the tests to not use the `opam config <weirdthings>` anymore

No, OPAM is not a build system.
Add a script to add library/syntax from ocamlfind to OPAM metadata

To use it:

$ opam-admin lib --infer <pkg>

Currently, just look at the list of uninstall targets. Could be completed to look into the archive directly.
Fix `opam-admin lib`
Fix urls.txt

This vastly improves the line-lexer and fixes escapes in urls.txt.
Ref: #1363
Don't reload urls.txt for each packages

this was a regression that was introduced when parallelising downloads:
workers wouldn't share there urls cache.

Also some optims in loading the file.
Fix complexity of OpamFilename.Set/Map
optim: skip costly computation of empty dependency cones
Merge pull request #1365 from OCamlPro/optim-urls

Some optimisations, mainly regarding loading of urls cache
Merge pull request #1361 from samoht/master

Towards a bridge with ocamlfind
Simpler build using OCamlMakefile
Fix travis scripts
Build & travis fixes
Remove prereqs from make 'install*' targets

so that it's safe to call them with 'sudo'
make: Install libs to the ocamlfind prefix rather than $(prefix)
Fixed the 'test' and 'doc' targets