Add installer scripts which download and install the scripts to run exaslct from a prebuild docker container

[tkilias]

Backgorund

• exaslct will be used in several repositories, such as the script-languages, the legacy-udfclient-* and later also in the repositories for each flavor
• at the moment exaslct only works on linux and needs at least a linux docker container to run on MacOS and likely also Windows
• as such we are going to distribute exaslct as a docker container which gets build for each commit to the main branch and will be published to docker hub
• we need a minimum set of scripts to run the docker container and mount all necessary directories into it
• these scripts need to be installed and updated in each repository that uses exaslct

Acceptance Criteria

• we need a single script which bootstraps the whole installation and which can install past, current and future versions of exaslct
  • the bestway to do this, is probably, by having a super simple bootstrap script which loads the actual install script for the requested version