Improve diagnostic messages for pkg-config.

Only pass known libraries to pkg-config. Fixes #274. ...

This is yet untested. Also disables calling pkg-config on non-Posix systems.

Fix usage of the selections file (was completely ignored) and improve diagnostic output.

Emit better error messages for unresolvable dependency trees.

Missing tilde

Enable library targets for LDC compiler.

Fix dependency resolution. ...

The "if (parent == root) return pidx;" line needed to be inside the "if(!matches" block.

Prefer version tags to branches when determining package versions using GIT.

Avoid querying the package registries repeatedly for invalid packages.

Optimize dependency version resolution when root dependencies fail.

Avoid internal exception when loading version selections.

Fix version overrides with a recursively matching target version.

Expire cache entries in RegistryPackageSupplier after one day.

Fix null pointer dereference in DependencyVersionResolver when no project is loaded.

Enable vibe.d based HTTP downloads, if possible.

Use URL and Path types of vibe.d if available for better interop.

Rename UpdateOptions->UpgradeOptions and move it to dub.dub.

Properly support path based version selections.

Make DependencyVersionResolver public for external use.

Fix validating the configuration graph. ...

getTopologicalPackageList(), which was used before, could yield a different set of packages.

block on ddox child process ...

- fixes SIGINT (ctrl+c) for 'dub -b ddox'

Let "*" match any version or branch. Fixes #151.

Fix an error in the dependency resolution due to a signed/unsigned comparison. See #285. ...

Also added some diagnostic output to the dependency resolution algorithm.

Make log parameters lazy instead of auto ref. ...

This enables passing arguments doing complex computations for debug messages without worrying about impacting execution speed when debug logging is disabled.

Resolve sub packages of the root package directly instead of using the package manager. Fixes #287.

Add path based sub packages to Package.m_subPackages, too.

Fix null pointer dereference in Project.this() when no package was found. Fixes #286.

Avoid exponential run time in the dependency resolution algorithm if possible. ...

When going through all combinations of package versions, all sub trees of the search space are now skipped for a conflicting node, as those are guaranteed to conflict anyway.

Handle packages with invalid package descriptions gracefully and improve diagnostic output.

Fix compilation on DMD 2.064.