dllmap for BitBlt in gdi32.dll
gdi32.dll redirection apply to non-windows only
[runtime] Handle native size of structs with explicit layout and min alignment smaller than default packing. Fixes #4510

The calculating the native size of structs with explicit layout we need to take into consideration the minimum alignment
needed and the packing asked.

If no packing is supplied, we should respect the minimum alignment. If packing is supplied we should use the minimum required.
Follow up on return intrinsics tightening the preprocessor checks and using the declared version of the intrinsic instead of declaring it ourselves.

Addressing a post-commit review by @alexrp.
[jit] Add a mono_get_jit_tls () helper function.
Merge pull request #735 from wtfrank/bitblt

dllmap for BitBlt in gdi32.dll
[xbuild] Return unescaped path from TaskItem.GetMetadata ("FullPath")

This is in accordance with the behavior in .NET. No matter what string you feed
the ctor (escaped or unescaped), GetMetadata("FullPath") always returns the
unescaped version.
Setup projects
Rename Mono.XBuild.Tasks.dll to Mono.XBuild.dll