Bugfix for github issue 2890.
Changing default behavior of vagrant up to enable "cableconnected" on bridged network devices
Applying bugfix for cableconnected issue to earlier releases of virtualbox 4.x series
Fix wording of upload permission error

SCPPermissionDenied expects a path, and this is most likely the
destination (to) and not source (from).

[#2804]
synced_folders/rsync: Install `rsync` on guest if needed

Add new `rsync_installed` and `rsync_install` guest capabilities
to detect and install `rsync`.

Also copy `rsync_pre` capability to all Unix guests.
core: Only load default and plugin Bundler groups to avoid dev deps
provisioners/file: Add unit tests for the config
provisioners/file: expand destination path if capable
provisioners/file: add unit tests for the provisioner
core: execute the specified Vagrant executable in pre-rubygems.rb
Make sure synced folder types are always symbols

This will make sure that plugins that define synced folders after this
config object has been finalized won't have trouble because of
forgetting to use symbols instead of strings.

References https://github.com/fgrehm/vagrant-cachier/issues/76
Add new version.txt used to generate installers
Make version 1.5.0.dev for semver

/cc @tmatilai - I modified the vagrant-installers to strpi this.
core: Force bundler usage if in Installer
guests: rename LinuxShellExpandFailed error to ShellExpandFailed

Make the error generic for all guests (`DarwinShellExpandFailed` didn't
even exist) and not tied to synced folder.
guests/{free,net,open}bsd: Add `shell_expand_guest_path` capability
Merge pull request #2925 from fgrehm/ensure-synced-folder-types-are-symbols

kernel/v2: Make sure synced folder types are always symbols internally
Merge pull request #2922 from tmatilai/file_provisioner_expand_path

provisioners/file: expand destination path if capable
kernel/v2: allow IPs to end in ".1" [GH-2914]
Merge pull request #2906 from frosario/cable_connected

providers/virtualbox: connect cable for bridged networking
update CHANGELOG