FeatureSummary: Allow to combine and reorder values for the "WHAT" option

For example it is now possible to do:

  feature_summary(WHAT ENABLED_FEATURES
                       DISABLED_FEATURES)

That produces an output like:

  --
  -- The following features have been enabled:

   * Feature1
   * Feature2

  -- The following features have been disabled:
   * Feature2

Skipping the lists that are empty.

Without this patch this would require to do:

  message(STATUS "")
  feature_summary(WHAT ENABLED_FEATURES
      DESCRIPTION "The following features have been enabled:")
  feature_summary(WHAT DISABLED_FEATURES
      DESCRIPTION "The following features have been disabled:")

And empty lists would not be skipped.

The behaviour when WHAT has a single argument (ALL or any option) is
unchanged.
FeatureSummary: Add unit tests
CMake Nightly Date Stamp
Qt4: Fix moc command dependencies for incremental build.
Merge topic 'fix-Qt4-moc-command-depends' into next

dd015e4d Qt4: Fix moc command dependencies for incremental build.
Qt4: Fix moc command dependencies for incremental build.

Since commit v2.8.12~327^2 (Qt4Macros: Allow specifying a TARGET
in invokations of macros., 2013-02-26), a parameters file is
populated with moc arguments at generate-time.

When the compile definitions or include directories change, the
parameters file is updated but moc is not re-run in response.

Fix that by making the moc invocation depend on the parameters file.

Reported-At: https://bugreports.qt-project.org/browse/QTBUG-36970
Merge topic 'fix-Qt4-moc-command-depends' into next

ee9410a9 Qt4: Fix moc command dependencies for incremental build.
CMP0017: Fix check when including from CMake source tree

When running CMake from the build tree the CMAKE_ROOT is the
entire source tree.  Fix the CMP0017 check to be specific to
the Modules/ directory under CMAKE_ROOT so that Tests/ does
not count.  Fix the FindPackageTest modules to include FPHSA
by full path from CMAKE_ROOT so that they do not include the
local FPHSA which reports an error meant to test that CMP0017
works.
Merge topic 'fix-CMP0017-check' into next

7e187eea CMP0017: Fix check when including from CMake source tree
Revert topic 'dev/faster-evis'

It will be revised and restored again.
Merge topic 'dev/faster-evis' into next

4d02ac9a Revert topic 'dev/faster-evis'
Help: Update CMAKE_SYSTEM* and CMAKE_HOST_SYSTEM* documentation

Update to documentation for HOST/TARGET system related variables to be
consistent with current functionality.
Merge topic 'doc-host-target-vars' into next

06986afc Help: Update CMAKE_SYSTEM* and CMAKE_HOST_SYSTEM* documentation
74b982ce CMake Nightly Date Stamp
cmake: Fix --check-build-system argument count check (#14784)

This internal option requires two arguments, not just one.  Fix the
argument count required to recognize the option.
Merge topic 'fix-check-build-system-crash' into next

3504f9b9 cmake: Fix --check-build-system argument count check (#14784)
KWSys 2014-03-03 (b1916e0a)

Extract upstream KWSys using the following shell commands.

$ git archive --prefix=upstream-kwsys/ b1916e0a | tar x
$ git shortlog --no-merges --abbrev=8 --format='%h %s' 606d7d6f..b1916e0a
Adrien Destugues (1):
      b1916e0a SystemInformation: Update CPU count code for Haiku

Clinton Stimpson (3):
      0d8ef429 Encoding:  Help enforce the use of wide apis on Windows.
      cfbc1cc8 FStream: Remove unused basic_filebuf declaration.
      b3b20cc0 FStream: Add ability to detect BOM.

Jiri Malak (1):
      e66d99b8 SystemTools: Fix compilation with Open Watcom

Matt McCormick (1):
      b3db597b SystemInformation: Mark EXECINFO_LIB as advanced

Change-Id: I154a92be7a3ec4c7c12bffbfcd7b50ec7de53c5f
Merge branch 'upstream-kwsys' into update-kwsys
Merge topic 'update-kwsys' into next

7db95df3 Merge branch 'upstream-kwsys' into update-kwsys
f096786d KWSys 2014-03-03 (b1916e0a)
Revert "Qt4: Fix moc command dependencies for incremental build."

This reverts commit ee9410a94e2a1a02b3183848bce9e48eb602c4bd.

This requires evaluation of the DEPENDS as generator expressions,
which is not yet possible.
Merge topic 'fix-Qt4-moc-command-depends' into next

1a2f178c Revert "Qt4: Fix moc command dependencies for incremental build."