Merge branch 'lectures2021'

lectures/README.md

lectures/build.gradle

lectures/revealjs/01-course-intro.adoc

lectures/revealjs/02-software-development.adoc

lectures/revealjs/03-dev-and-scm.adoc

lectures/revealjs/04-git-demo.adoc

lectures/revealjs/05a-admin-issues.adoc

lectures/revealjs/06-build-tools-and-some-testing.adoc

lectures/revealjs/07-gitlab.adoc

lectures/revealjs/08-workflow-example.adoc

lectures/revealjs/09-documentation.adoc

lectures/revealjs/10-unit-testing.adoc

lectures/revealjs/11-code-quality.adoc

lectures/revealjs/12-modular.adoc

lectures/revealjs/13-solid-uml.adoc

lectures/revealjs/14-git-gitlab.adoc

lectures/revealjs/17-rest-api.adoc

lectures/revealjs/19-common-issues.adoc

lectures/revealjs/agiletools.adoc

lectures/revealjs/ci.adoc