Read box file in binary mode for checksum
Merge pull request #3045 from bmorg/master

core: read box file in binary mode for checksum
Update CHANGELOG
core: Vagrant.installer_embedded_dir
core: load system plugins if they are installed
core: add tests fornew systems path for plugin manager
core: plugin manager marks system gems as system
commands/plugin: list notes system gems
core: better error if attempting to uninstall system plugin
core: safer dup checks for synced folders