fixes support for unc path

fixes unc path error

Fix object directory for -op switch in the VisualD generator and prepare for different project file directories. ...

Future versions may choose to put the project files in the .dub directory (the solution file will still stay in the project's root directory).

Change the file dictionary to a file list for "dub describe"'s output.

Implement a first version of "dub describe".

Improve JSON pretty printing and appending.

Log warnings/errors/diagnostics to stderr instead of stdout.

Implement the "noDefaultFlags" build requirement. Fixes #68.

Write the "optional" field out as bool instead of string.

Add build workaround also for LDC.

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

Preparing for the new std.process in Phobos.

Attempt to replace the Ubuntu fix by a more generic fix that does not depend on a distribution name. See also #71.

Silence lsb_release output.

Syntax error fix.

Redo build script to directly call the compiler + limited compiler auto-detection. ...

No rdmd is necessary anymore and the call to "uname -a" has been changed to
"lsb_release -i" to detect the distribution more reliably. This needs to be
properly fixed, though, by looking at the GCC version or by using a
workaround that works on older _and_ newer versions.

Fix LDC linker flag specification and add workaround for conflicting object file names.

Use separate compile/link only for dmd (and not for ldmd and gdmd).

Use -d-debug instead of -debug for LDC.

Fix compilation with latest LDC.

Attempt to fix handling of "-Wl" flags returned by "pkg-config".

Changed the windows build script to directly call the compiler instead of rdmd. ...

The compiler used can be customized by setting the DC environment variable ("dmd" is the default and "gdmd" or "ldmd" are the most likely alternatives).

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

Move download() to dub.utils and remove dub.internal.vibecompat.inet.urltransfer.

Compile fix for DMD 2.053 beta.

Not available optional dependencies are not wared upon.

Updating optional dependencies themselves, when they are available.

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

Added "dub list-system" and "dub list-user".

Package updating could work with optional dependencies.