Chandan Singh authored Oct 05, 2018 and Chandan Singh committed Oct 08, 2018

In !857, we added `contrib/bst-docker-import` script but it has a small
issue that some of logs go to stdout while others go to stderr. Fix it
so that all logging is done on stderr.

bst-docker-import: Consistently use stderr for all logs

See merge request !863

The code was creating the cwd folder but when the workspace was
mounted in to the buildroot it was hiding the folder created in it
behind the bind mounted workspace.

However by using the bubblewarp `--dir` directive to ensure that cwd
exists we can cover both workspace and non workspace situations with
the same method.

Build stream was only creating command-subdir for non workspace builds
this has now been fixed, and this regression test should support the
feature.

Adding the conf-root variable makes creating out of source builds
slightly easier.

Three examples covering out of source builds for:
 * basic autotools
 * basic cmake
 * autotools from a folder inside the source folder

This is also the first cmake example.