uncrustify (uncrustify.sourceforge.net) is applied to changed files prior to
commit.

This feature is off by default.  To enable this behavior, set

  git config hooks.uncrustify true

By default, the behavior of git-mergetool is used to review the changes
uncrustify makes before they are added to the commit.  For more information on
this behavior, see

  git help mergetool

KWStyle is run on the changed C++ files and the commit is aborted if the files
do not pass the test.  A file similar to the original is saved with a '*.kws'
extension so that line numbers referenced in the error message can be examined.

The test is off by default.  To enable this behavoir, set

  git config hooks.KWStyle true

Project specific uncrustify and KWStyle configuration files are set with 'git
config'.  For example,

  git config hooks.uncrustify.conf path/to/uncrustify.conf
  git config hooks.KWStyle.conf path/to/KWStyle.conf
  git config hooks.KWStyle.overwriteRulesConf path/to/overwrite.conf # optional

If the appropriate values have not been set, die() is called.  An
optional KWStyle overwrite rules file can also been configured.

The files on which to run the style checks must also be identified in the
repository's '.gitattributes'.  For example,

  *.h    hooks.style
  *.cpp  hooks.style

Or, to only enable a subset of style hooks,

  *.h    hooks.style=KWStyle
  *.cpp  hooks.style=KWStyle,uncrustify

Change-Id: Ia6b2d4136af3002eb0ec5d36f03c50df928917f4