Defer rubyzip/CSV loading and drop the unused logger require

[pcai]

Reimplementation of the load-time cleanup from @tas50 (Tim Smith) in chef/chef-winrm-fs@643d72b.

• require "zip" / require "csv" move from load time to first use (inside FileTransporter#initialize and #parse_response respectively), so requiring winrm-fs no longer pulls in rubyzip and CSV up front.
• TmpZip requires zip in #initialize instead of at load.
• Drops the unused top-level require "logger" in lib/winrm-fs.rb (nothing references Logger at load).

Note: Zip.unicode_names = true stays in FileTransporter#initialize rather than moving elsewhere, because it affects the archive SHA1 used for the dirty check.