Composer-Setup 4.7.0

• Stopped uninstall removing Composer\vendor\bin from the user path if there is another composer files directory in the path (ie from a subseqent Developer mode installation).
• Improved shell proxy handling, in case of CDPATH conflicts.
• Improved error reporting, making use of stderr now that PHP uses it better.
• Added output from stdout and stderr to the log file for better troubleshooting.
• Unattended SYSTEM installations no longer write data to the system user profile.