chore: add LICENSE

docs: add README.md documentation

feat: add docker with PORT variable as possible ARG

feat: add port definition by environment variable

feat: remove docker files from main-branch

feat: add docker with compose to the project

docs: add documentation for Update Opening

docs: add documentation for List Openings

docs: add documentation for Show Openings

docs: add documentation for Delete Opening

docs: add documentation for create Opening

feat: add swagger configuration

feat: add list openings handler logic

feat: add update handler logic

feat: add show opening handler logic