motivation: prepare for swift 5.8

changes: add docker compose setup for nightly 5.8

…ndler example (#286)

Improve archive command documentation 

* Show the options that the new `archive` plugin provides to customize the operation behavior.
* Provide an example with the `archive` command taking two parameters

Use issue Report v2: Issue template using the GitHub Forms syntax.

motivation: examples can be confusing since they use relative path to the library for CI purposes

changes:
* update examples to use the library URL, expect when env variable is set for CI purposes
* rename docker compose job to test-examples since it is more accurate

* Swift 5.8 docker images are available

* Add docker-compose file for Swift 5.9

* Fix image name

motivation: align CoC across the swift project

changes: change CoC to link to the swift.org version

motivation: swift 5.9 ships with builtin backtrace support \o/

changes:
* remove the dependency on swift-backtrace when using swift 5.9 or above
* conditionalize the call to Backtrace.install to relevant versions only

improved getting started documentation, with DocC

motivaiton: test for upcoming 5.10 release

changes: add docker setup for stable 5.9 and nightly 5.10

motivation: sometimes, you need to use a customized local docker image and `docker pull` don’t have to be called

changes:
* add `--disable-docker-image-update` plugin flag to disable `docker pull` call

motivation: address warnings

changes:
* remove pre-concurrency flag when not longer needed

Improved getting started documentation, with DocC

…310)

Motivation:

Provide the flexibility for custom initialization of the HandlerType as this will often be required by higher level frameworks.

Modifications:
* Modify the LambdaRuntime type to accept a closure to provide the handler rather than requiring that it is provided by a static method on the Handler type
* Update downstream code to use HandlerProvider
* Update upstream code to support passing Handler Type of Handler Provider
* Add and update tests

Originally suggested and coded by @tachyonics in #308