s/extremely to/extremely easy to/
Merge pull request #575 from ciarand/feature/fix-typo

Fix typo in documentation
builder/amazon/*,builder/openstack: properly scrub sensitive [GH-554]
communicator/ssh: buffer file on disk to read length [GH-561]
builder/virtualbox: allow disabling guest addition uploading
website: docs on disabling guest additions
command/fix: add fixer to auto set guest_additions_mode
update CHANGELOG
command/fix: add synopsis option to fixers

This will be used in help output and such later
Merge pull request #542 from phyrex1an/patch-1

website: propose additional IAM Role Actions
common: downloads can be HTTPS [GH-587]
packer: builder prepare can return warnings
packer/rpc: implement new warnings interfaces
packer/rpc: use packer.MockBuilder for tests
packer/rpc: test warnings with builders
packer/plugin: new Builder interface
builder/amazon/*: warnings
builder/all: update to warnings
command/validate: output warnings
command/build: get command passing