Windows installation guide

Downloading via file_get_contents & creation of BAT file
removed composer download
Merge remote-tracking branch 'pborreli/typos'
Merge remote-tracking branch 'cloakedninjas/master'
Add setup instructions
Reorganize intro page a bit
Do not send an empty list of packages to the default policy, fixes #1259
Fix deletion of vcs dirs, fixes #1260
Fix windows setup instructions, fixes #1262
Update vendors
SvnDriver fixes
fixed a typo
Fixed library installer windows .bat generator
Fix var override, fixes #1061
Merge remote-tracking branch 'bamarni/patch-4'
Add --check to troubleshooting docs
Output error only on real errors, not any stderr output
Fixed package name for stability test in ComposerRepository
Merge remote-tracking branch 'hason/composer_repository'
Report typos in package name if no version matches