Add xcm-simulator (#102)

* feat: add xcm simulator for trappist use cases

* test: add (dmp) teleport test

* test: add (ump) teleport test

* test: add two-hop reserve transfer test

* refactor: rename crate and remove unused code

* docs: add xcm-simulator overview

* ci: add simulator workflow

* docs: fix xcm simulator test command

* docs: update readme with suggested improvement

Co-authored-by: bernardo <[email protected]>

* docs: update readme with suggested improvement

Co-authored-by: bernardo <[email protected]>

* docs: add link to integration-tests

* docs: fix simulator test command

Tests are run in parallel by default, resulting in mixing of logging output in console

* ci: adjust simulate workflow

* ci: add cache handling for nextest install

* ci: improve nextest install

* refactor: rename parachain to template to better describe intention

Co-authored-by: bernardo <[email protected]>