(GH-215) The term 'false' is not recognized

A regression introduced in
abe92f3
which is just in 0.9.9.3 that was attempting to solve other issues
caused choco to stop working completely in some versions of PowerShell,
which have stricter requirements for setting booleans.

Without this fix, chocolatey will continue to be unusable

src/chocolatey.resources/helpers/chocolateyInstaller.psm1

@@ -21,11 +21,11 @@ if ($env:ChocolateyEnvironmentVerbose -eq 'true') { $VerbosePreference = "Contin
 
 $installArguments = $env:chocolateyInstallArguments
 
-$overrideArgs = false
-if ($env:chocolateyInstallOverride -eq 'true') { $overrideArgs = true }
+$overrideArgs = $false
+if ($env:chocolateyInstallOverride -eq 'true') { $overrideArgs = $true }
 
-$forceX86 = false
-if ($env:chocolateyForceX86 -eq 'true') { $forceX86 = true }
+$forceX86 = $false
+if ($env:chocolateyForceX86 -eq 'true') { $forceX86 = $true }
 
 $packageParameters = $env:chocolateyPackageParameters