Add unittest to test collection of C sources and headers

make build names much smaller (#2589)

Merge remote-tracking branch 'upstream/stable' into merge_stable

reduce dependency on the working directory ...

Improves library API usage and bugs with the build generator

Don't assume the cache path is relative to CWD ...

It is no longer in `$PACKAGE_ROOT/.dub`, but in a central location.

Remove GeneratorSettings.direct as it is never set

Use a central build cache for all build artifacts ...

Currently the central build cache is not configurable,
but as most build artifacts end up in `~/.dub/packages/` anyway,
this will be a positive change for users.

Move computeBuildID outside of BuildGenerator ...

It does not use anything from 'this', only its input parameters.
Additionally, change the order so it is usable with UFCS.

Replace all instances of mkdirRecurse with ensureDir ...

All usages actually want to ensure the directory is present,
and don't care about having a separation between existence check
and creation.

Copy all dynamicLib deps extra files for root packages with `none` targetType ...

To support 'framework' use cases - a dummy root package depending on a bunch
of dynamicLibs, where all extra files are to be copied to the output dir.

Copy extra files of (direct & indirect) dynamicLibrary deps to root package output dir only

Windows: Copy .lib files from DLL deps only ...

One aspect of issue #2377 - don't copy static libs. And only copy
import .lib & .exp if the dependee is a DLL too.

Support --temp-build also in `dub build` (#2428)

Windows: Don't copy import .lib & .exp files for executables ...

One aspect of issue #2377 - copy those for DLLs only.

Forward flag `--color={on,off}` to compiler calls (#2382) ...

When the user sets the color mode explicitly,
we forward it to the compiler for consistency,
while making sure it doesn't impact the build cache ID.

Fix #2348 Crash when describing postBuildCommands

Use SHA256 in place of MD5 in computeBuildName

improve some output coloring ...

See #2347

Address review by WebFreak001.

Keep logging functionality out of the public API as requested in https://github.com/dlang/dub/pull/2124#issuecomment-813016939.

Fix/Update some tests and make some info messages more similar to original version of Dub

Fix indentation style, now using tabs

Fixed blue color missing for config in up-to-date

Making the output prettier - first changes

New logging module - initial functionality ...

The new module replaces dub.internal.vibecompat.core.log by using the
same function names, but implementing colored output and the left
fixed-width tag. Overloaded functions are provided to output colored
text.

Still missing initLogging() and non-TTY stdout/stderr detection

Make Project.addTestRunnerConfiguration() accept a const GeneratorSettings argument

Refactor checks for platform is Windows into a method on BuildPlatform

Fix issue 2258 and copy the build artifacts to the target directory

Define the $DUB_BUILD_PATH variable. ...

The `$DUB_BUILD_PATH` variable is now defined inside the `postBuildCommands`
section. It contains the absolute path in which the package was built, and can
be used to copy by-products of the build process to their intended locations.

move command variable substitution to execution ...

This is needed as commands that need to be run need to have generator
settings available before running to avoid inconsistencies with
environment variables passed to the actually ran program and variables
used in substitution.

Fixes #2192

Fixes pre/postGenerateCommands inconsistently using dub environments
(execution was substituted including buildEnvironments, but shell cmd
did not get the build variables for substitution) - now both get
the build variables. Solved by removing code duplication. (env building)

This commit changes the behavior of `dub describe` so that describing
commands settings no longer substitutes variables. Before, known
variables would have been replaced in the output and on unknown
variables `dub describe` would fail with an error
`Target 'x' doesn't exist`

Now exposes some previously private project.d processVars functions