Fix deprecation warning using raw str

[sloretz]

This fixes a deprecation warning when building ament_lint_cmake on windows 10 using python 3.7.3

C:\ros2_ws\build\ament_lint_cmake\build\bdist.win-amd64\egg\ament_lint_cmake\cmakelint.py:124: DeprecationWarning: invalid escape sequence \.
  package = re.sub('^Find(.*)\.cmake', lambda m: m.group(1), package)
C:\ros2_ws\build\ament_lint_cmake\build\bdist.win-amd64\egg\ament_lint_cmake\cmakelint.py:335: DeprecationWarning: invalid escape sequence \.
  name_match = re.match('Find(.*)\.cmake', os.path.basename(filename))

[dirk-thomas]

Have these changes been contributed upstream? If not I would recommend that and once they have been accepted we can pull an updated version.

[sloretz]

I didn't realize this file was taken from another repo. It looks like cmakelint is available on pip PyPI, any reason not to use that?

[dirk-thomas]

It looks like cmakelint is available on PyPI, any reason not to use that?

We need it to be a Debian package in order to depend on it in a Debian package.

[hidmic]

Hmm, isn't this already in master?

[sloretz]

Replaced by #144