Merge branch '0.9.22' ...

Conflicts:
	source/dub/dub.d
	source/dub/generators/build.d
	source/dub/generators/generator.d
	source/dub/package_.d

Avoid exception in up-to-date check for non-existent source files and trigger rebuild instead.

Avoid '/', '\\' and ':' in build path when --compiler specifies a complex path. Fixes #412.

Merge pull request #381 from Geod24/ldc-support ...

Various small fixes

Various small fixes ...

- fix computeBuildID for --compiler=/my/path;
- dub compiled with ldc tried to invoke ldc as default binary instead of ldc2;
- dmd: Don't generate anything;
- gdc: Do not link, only generate an object;

In copyFiles, check if entry is glob before treating it as such

Improve warning message when --rdmd is used without a "mainSourceFile". ...

See also #396.

Added glob support to copyFiles

Fix trying to copy copyFiles where source==destination.

Step one of abstracting package description format

create symlinks instead of copying cached build files

Implement separate linking on gdc

Fix output flags for compilers != dmd

Added singleFile support

Add a --temp-build switch to force building in the TEMP folder. Fixes #294.

Only add platform flags for targets that generate an actual binary. Fixes #346.

Removed trailing whitespace

Converted line endings from CRLF to LF

Use "dub.json" instead of "package.json" in documentation

Fix isUpToDate for sub packages

Fix up-to-date check for intermediate dependencies. ...

In a dependency chain with static libraries b and c (a->b->c), changing something in c didn't trigger a rebuild of b, but only of c and a.

Display the compiler binary with invoking the compiler for separate compilation. See #326.

Fix orphan format specifier.

Do not build dependencies of static libraries. Fixes #316.

Add the --build-mode switch to control how the compiler and linker are invoked.

Don't run postBuildCommands for up to date targets.

Process variables for pre-/postGenerateCommands.

Print the version of each target during the build.

Fix copying "copyFiles".

Create target directory if necessary. Fixes #261.