(GH-17) Allow keeping c:\chocolatey when explicit
(GH-17) Allow keeping c:\chocolatey when explicit

When $env:ChocolateyAllowInsecureRootDirectory = 'true' leave the
directory intact and install the files.

TheBigBear/choco,TheBigBear/choco,harish123400/choco,bazzilic/choco,jberezanski/choco,b1thunt3r/choco,dtgm/choco,jamessingizi/choco,Apteryx0/choco,finchd/choco,kouweizhong/choco,dtgm/choco,ewilde/choco,darrelmiller/choco,Annih/choco,sideeffffect/choco,bc3tech/choco,ewilde/choco,vcarrera/choco,sideeffffect/choco,TheBigBear/choco,Annih/choco,bc3tech/choco,harish123400/choco,alephnaughty/choco,ShwoognationHQ/choco,mwrock/choco,bazzilic/choco,jamessingizi/choco,christianrondeau/choco,darrelmiller/choco,mwrock/choco,hagb4rd/choco,alephnaughty/choco,vcarrera/choco,eeevans/choco,eeevans/choco,raisercostin/choco,jberezanski/choco,Apteryx0/choco,finchd/choco,christianrondeau/choco,b1thunt3r/choco,raisercostin/choco,jberezanski/choco,kouweizhong/choco,dshaneg/choco,dshaneg/choco,hagb4rd/choco,ShwoognationHQ/choco