README.md: Remove nesting version-control/svn

There's no need to hard-code target directories in this repository.
Anyone consuming this material can use submodules and pick their own
target directory.

diff --git a/version-control/svn/README.md b/README.md
similarity index 100%
rename from version-control/svn/README.md
rename to README.md

diff --git a/version-control/svn/instructor.md b/instructor.md
similarity index 100%
rename from version-control/svn/instructor.md
rename to instructor.md