Revert "Only try to download installer if it's present"

This reverts commit 5d36c1f58104652fb81c215bdd587a3190c4e359.
Add in ArchiveCollection class
Use ArchiveCollection in PEBuild::Archive for display
Merge branch 'archive_set'
Merge pull request #17 from trlinkin/revert_5d36c1f

Revert "Only try to download installer if it's present"
Remove unused exception class
Use Vagrant home_path for archive_directory
Expand path relative to env.home_path
Include archive_collection in archive
Version unpacked archive in idempotent message
Clean up pe_bootstrap error messages
Change version to 0.1.0

This isn't ready for a 1.0.0 release, and I haven't cut a final release.
It's ugly, but in the end it's not the worst thing ever.
(vagrant-pe_build #18) Add license to gemspec

This closes GH-18