4.13 version updates

Bump versions for:
- org.eclipse.core.externaltools
- org.eclipse.core.variables
- org.eclipse.debug.examples.core
- org.eclipse.debug.examples.ui

Required for https://git.eclipse.org/r/#/c/142394/

Change-Id: I44573999ecb9f99c2be39110434a623b32521a2e
Signed-off-by: Karsten Thoms <karsten.thoms@itemis.de>
6 files changed