Merge branch '3.3-maint'

Merge branch '3.3-maint'

* 3.3-maint:
  Document how automatic cleanup works
  Make ccache -c/--cleanup not take limit_multiple into account
  test: Fix printing of failure reason with glob characters
  Fix grammar in cleanup_* function names
  test: Unset all CCACHE variables in environment
  cleanup: Improve logging
  test: Check more cases of path normalization
  Don't overwrite cached .d file with a version with absolute paths
  test: Fix verbose printing of test case name with space
  Update NEWS
  Don't use cache when building precompiled header with changed deps
  Always use include DEFAULT_SLOPPINESS when overriding CCACHE_SLOPPINESS