Fix null pointer dereference in Project.this() when no package was found. Fixes #286.
Add path based sub packages to Package.m_subPackages, too.
Resolve sub packages of the root package directly instead of using the package manager. Fixes #287.
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.
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.
Add the test packages to the Travis CI script. See #287.
Let "*" match any version or branch. Fixes #151.
block on ddox child process

- fixes SIGINT (ctrl+c) for 'dub -b ddox'
Merge pull request #291 from MartinNowak/blocking_ddox

block on ddox child process
Fix validating the configuration graph.

getTopologicalPackageList(), which was used before, could yield a different set of packages.
Make DependencyVersionResolver public for external use.
Properly support path based version selections.
Rename UpdateOptions->UpgradeOptions and move it to dub.dub.
Use URL and Path types of vibe.d if available for better interop.
Enable vibe.d based HTTP downloads, if possible.
Fix null pointer dereference in DependencyVersionResolver when no project is loaded.
Expire cache entries in RegistryPackageSupplier after one day.
Fix version overrides with a recursively matching target version.
Avoid internal exception when loading version selections.
Use a version based vibe.d dependency.