Release 6.0.0-alpha.8 #1708

Waiting on:

• Side-by-side Unix packages Redesign Linux packages for side-by-side version installation #1309
• Ubuntu 16.04 packages Create Ubuntu 16.04 packages #1433
• Help fixes Fixing get-help on Linux #1695 (issues get-help get-process throws System.NullReferenceException #1611 and Add current help maml files for Linux/OS-X builds #1469)
• Man page Adding Man Page For PowerShell #1666

Tasks:

• Write changelog
• Update releasing docs
  • build from /powershell for debug symbols
  • document side-by-side design
  • Release configuration for Windows
• Update readme links
• Update installation docs
  • RHEL has been tested at least once
  • Ubuntu 16.04 installation
• Build and test Ubuntu 14.04 package
• Build and test Ubuntu 16.04 package
• Build and test CentOS 7 package
• Build and test OS X package
• Build and test MSI package
• Create new GitHub release with changelog and packages
• Increment AppVeyor build number