The test_server application has previously been deprecated.

In OTP 19, we will move relevant parts of test_server into the
common_test application. Test suites that include test_server.hrl
must be updated to include ct.hrl instead. Test suites that include
test_server_line.hrl must removed that inclusion. Test suites that
call the test_server module directly will continue to work in OTP 19.

The test suites for Erlang/OTP are built and executed in exactly
the same way as previously.

Here are some more details.

The modules test_server*.erl and erl2html2.erl in lib/test_server/src
have been moved to common_test/src.

The test_server.hrl and test_server_line.hrl include files have
been deleted. The macros in test_server.hrl have been copied into
lib/common_test/include/ct.hrl.

The ts*.erl modules and their associated data files in
lib/test_server/src has been been moved to the new directory
lib/common_test/test_server. The ts* modules are no longer built
to lib/common_test/ebin. They will only built when 'make release_tests'
is executed.

The test suite for test_server has been moved to lib/common_test/test.

The rest of the files have been deleted.

Sometimes we install *.erl files. Some these files include a private
*.hrl files, so in order to make these *.erl files usable we have to
install these private includes as well.

Signed-off-by: Peter Lemenkov <lemenkov@gmail.com>

* nox/enable-silent-rules/OTP-10726:
  Implement ./otp_build configure --enable-silent-rules

With silent rules, the output of make is less verbose and compilation
warnings are easier to spot. Silent rules are disabled by default and
can be disabled or enabled at will by make V=0 and make V=1.

Update the interface for cross cover analysis (collection of cover
data over multiple tests) so it can be used via common_test and
directly with test server.

The concept of 'application' in the cross cover interface is removed
and replaced with an arbitrary Tag=atom() which identifies a test run.