Using pik from %PROGRAMFILES% makes troubles

[voxik]

C:\>pik in 1.9.2
INFO: Installing ruby-1.9.2-p136

INFO: Downloading:  http://rubyforge.org/frs/download.php/73723/ruby-1.9.2-p136-i386-mingw32.7z
      to:  C:\Users\vita\.pik\downloads\ruby-1.9.2-p136-i386-mingw32.7z

INFO: Extracting:  C:\Users\vita\.pik\downloads\ruby-1.9.2-p136-i386-mingw32.7z
      to:  C:\Users\vita\.pik\rubies\ruby-1.9.2-p136

C:\Program není názvem vnitřního ani vnějšího příkazu,
spustitelného programu nebo dávkového souboru.
      Extraction complete.
Couldn't find a Ruby version at C:\Users\vita\.pik\rubies\ruby-1.9.2-p136\bin

I would say that the issue is somewhere around this line: https://github.com/vertiginous/pik/blob/master/lib/pik/installer.rb#L62 However, it is strange that I cannot reproduce similar error using IRB, i.e:

C:\>c:\Users\vita\.pik.bak\rubies\Ruby-192-p136\bin\irb
irb(main):001:0> system "c:/Program Files (x86)/pik/7za.exe"
=> nil
irb(main):002:0>

produces no output ...

[vertiginous]

Oddly, I can't reproduce either, but I'm fairly certain that wrapping the 7zip path in quotes will fix this. I did that in a8555aa2149d4b32e140e604205b9d4adddaf6ee. I'll try to publish a new pre-release file today.