GNUInstallDirs: Fix CMAKE_INSTALL_LIBDIR on Debian

When not installing in /usr (i.e. /usr/local) on Debian/Ubuntu, the
multiarch path is not in ldconfig path, and therefore libraries cannot
be found, unless the user manually modifies the files in
/etc/ld.so.conf.d, in order to include /usr/local/lib/<arch>.

This patch fixes this issue by using "lib/<arch>" only if the user is
installing the software in /usr, and uses "lib" in all the other cases.
Help: Fix typo in 'if()' command documentation

s/argumemnts/arguments/
Revert "Ninja: Avoid re-running CMake on next build after regeneration"

Revert commit 6fac24d7 (Ninja: Avoid re-running CMake on next build
after regeneration, 2014-01-09).  The files reported by the method
cmMakefile::GetOutputFiles() must cause CMake to re-run only if they are
missing and without considering a timestamp.  Therefore they cannot be
listed as outputs of the re-run rule or Ninja will re-run CMake every
time because the timestamp of configure_file outputs does not change.

Another solution will have to be found to the original problem.
Revert "Ninja: Track configured files so we can regenerate them."

Revert commit 4a6397a7 (Ninja: Track configured files so we can
regenerate them, 2013-06-17).  The files reported by the method
cmMakefile::GetOutputFiles() must cause CMake to re-run only if they are
missing and without considering a timestamp.  This is not the meaning of
the implicit dependencies field so Ninja re-runs CMake too often.

Another solution will have to be found to the original problem.
CMake Nightly Date Stamp
cmake-gui: Remember variable type in Add Entry

Store variable types together with their names in the variable completion
list so that the type is automatically recovered when you select a variable.

Keep variable names and types in separate lists.  This removes the :TYPE
string from completion list and the Name field and makes variable search
easier.  The variable names and types are now kept in two different
settings - AddVariableNames and AddVariableTypes.  Drop the old
AddVariableCompletionEntries setting.
Merge topic 'var-type-autofill'

cfec180d cmake-gui: Remember variable type in Add Entry
Merge topic 'revert-ninja_fix_rerun'

79859689 Revert "Ninja: Avoid re-running CMake on next build after regeneration"
Merge topic 'ninja_fix_rerun'

20e595ab Revert "Ninja: Track configured files so we can regenerate them."
Merge topic 'fix-help-if-typo'

5968b6e0 Help: Fix typo in 'if()' command documentation
Merge topic 'GNUInstallDirs_debian-multiarch-fix'

620939e4 GNUInstallDirs: Fix CMAKE_INSTALL_LIBDIR on Debian