Webscaff

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+ Add 'sys.pg.cluster_upgrade' and 'sys.pg.cluster_drop' commands.
+ Add 'sys.utils.os-upgrade' command.
+ Add 'sys.utils.screen' command.
+ Added 'sys.apt.autoremove' command.
+ Command 'rollout' now supports '--from-local' option.
+ New command 'run.venv.populate'.
* Exposed run.git.pull command.

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* Enabled sys.apt.upgrade command.

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* Fix 'run.initialize' command permission error.

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+ New 'cfg' command.
* Enhance 'run.initialize' command: save progress to be able to resume.
* Enhance 'sys.cat' command: add 'printout' param.

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* Workaround patchwork issue: invoke.vendor.six.

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+ 'cache_init' now just empties cache directory by default.
+ 'info' now prints out current user information.
* Bootstrap spooler directory with right permissions.
* Improved boostrap of Certbot.