* siri/test-ct_release_test/OTP-13390:
  Remove upgrade tests from stdlib_SUITE
  Add test of ct_release_test

The test cases minor_upgrade and major_upgrade used
ct_release_test. The point of the tests in stdlib was mainly to test
ct_release_test. ct_release_test produces a 'from-release' based on an
old version of the application under test (in this case stdlib) and
new versions of all other applications. But since it is not always a
good idea to load an old version of stdlib into a new emulator
(e.g. in the OTP-19.0 emulator), these tests are removed.

Instead new tests are added for ct_release_test in common_test.

* bjorn/cuddle-with-tests:
  io_SUITE: Don't fail on fast computers with rough timers

* henrik/doc-fixes:
  Fix typo in INSTALL.md
  Update README.md
  Fix typo in 'app' documentation
  s/is/are

* sverk/bad_printable_range:
  stdlib: Fix io_SUITE:bad_printable_range for windows

Since Windows 8 we are not allowed (in non elevated mode) to
write to hklm.

avoid os:cmd as it treats stderr different on windows.

On a computer which is fast, but with timers with low resolution,
the measured time for an empty queue could be zero, which could
cause the test case to fail.

Add a calibration function to scale up the amount the amount of
work so that the measured time will not be lower than 50 ms.