KWSys 2016-07-15 (f396bf43)

Code extracted from:

    http://public.kitware.com/KWSys.git

at commit f396bf43fc8a3e475e703acb99d629d123dbd003 (master).

Upstream Shortlog
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Brad King (2):
      e43689db SystemTools: Factor out environment storage class
      2aa7dd82 SystemTools: Do not free buffer passed to putenv("A=") on Windows

Dāvis Mosāns (4):
      19c31914 SystemTools: Abstract environment storage character type
      61301786 SystemTools: Tweak GetEnv/PutEnv implementation layout
      85920d53 SystemTools: Teach GetEnv/PutEnv to use correct encoding on Windows
      f396bf43 SystemTools: Add HasEnv function