Improve error message for non-conformant package names. See #89.

Improve error message for unknown dependencies.

Quick-fix for the VisualD generator and upwards inherited version identifiers. ...

version identifiers were only inherited downwards, but upwards inheritance is needed for example for VibeCustomMain.

Introduce TargetType.none, fix handling of non-target project's dependencies and avoid continuous reinstalls of referenced sub-packages.

Rename log levels to be in line with the latest vibe.d versions.

Fix fetching of "sub:packages".

Avoid file-not-found exceptions when constructing Package-s with no valid path.

Improve diagnostic output when trying to get metadata.

Disable automatic upgrade of packages as it is currently broken. ...

This only ever worked for project locally installed packages, which are not supported anymore.

Avoid reloading local packages multiple times during a single run.

fixed uninstallation

Made "dependencies" a per-configuration setting instead of a purely global setting.

When conflicting dependencies where current in a project and its dependencies, dub could get into an infinite update loop. ...

This was because one package to be used was added to the graph, which then spawned a missing package for another dependency, because of not matching versions. These versions could then toggle forth and back.
This is now solved by aborting the dependency graph resolving process when conflicts are found. As the dependencies are resolved from the outermost to the innermost, this will propably hide some deeper conflicts, but then again show more user relevant conflicts first.
This does not resolve the question on what to do when merging ">=0.13.4" with "~master". But this can be resolved later on.
Fixes #72.

Add support for DUBPATH and "add-path" + change the default installation location to the DUB user path. Fixes #64. ...

This change allows to specify a number of directories in addition to the system and user DUB package directories to search for local packages.

Full list of changes:

 - Add support for the DUBPATH environment variable (a (semi-)colon separated list of paths)
 - Add support for "dub add-path" and "dub remove-path" to add static search paths
 - The branch of local packages with no "version" field in their package.json is now inferred using "git rev-parse"
 - The structure of the user/system package directories is changed from "packages/<packname>/<packver>" to "packages/<packname>-<packver>"
 - There is no project local package directory (".dub/packages") anymore - packages are instead installed to the user package directory by default
 - Upgrading and uninstallation is partially broken in this commit - will be fixed later

Implement a first version of "dub describe".

Add warning for package names with upper case letters, but handle them gracefully.

VisualD generator: Fix x64 builds and avoid building header only dependencies.

Compile fix for DMD 2.053 beta.

Updating optional dependencies themselves, when they are available.

Fixing issues in getTopologicalPackageList and getPackageConfigs because of added "optional" flag for Dependencies.

Package updating could work with optional dependencies.

Fix recursive determination of sub configurations. ...

See also #65.

Fix build settings for dependencies in the VisualD generator. ...

Paths were relative to the dependency package path rather than the main package path where the project file is generated. Also, versions and other build settings were not only inherited from dependency to dependee, but also the other way around.

Move all source files outside of "dub" to "dub/internal".

Implemented "buildRequirements" as a way to avoid certain compiler settings for specific code bases. ...

See also #61.

Support "-ddoxFilterArgs" field to control how --build=ddox filters documentation entities.

Improve output of the dflags warning message. Fixes #54.

Always upgrade branch based dependencies. Fixes #55.

Fix building in directory without package.json.

Fixed recursive configuration deduction and improved error messages for invalid package.json files.