Release updates (#102)

* Update RELEASING.md

* Use "uname -m" as "--machine" doesn't work on Darwin

* Update Dockerfile to use swift 5.10

* Update versions for new release

* Text update

* Update to swift 5.10

Release updates (#102)

* Update RELEASING.md

* Use "uname -m" as "--machine" doesn't work on Darwin

* Update Dockerfile to use swift 5.10

* Update versions for new release

* Text update

* Update to swift 5.10

swiftly-install 0.3.0 (#88)

Support installation on alternative platforms (#63)

Pin version of Swift used for building releases

Always disable package-manager confirmation when installing system de…

…pendencies (#56)

Confirmation from the underlying package manager is redundant, since the swiftly installer already asks the user if they'd like to install system dependencies. Additionally, piping the install script from curl into a bash shell hangs when the package manager asks for input, and this fixes that.

Install system dependencies in swiflty-install.sh (#54)

Temporarily disable the list-available command

The current WIP implementation doesn't take platform into account when
listing available releases, which means it can print releases that are
not actually available for a given platform.