added GDCR 2018 for Leipzig/Germany
added GDCR 2018 for Leipzig/Germany

coderetreat/coderetreat.github.io,svenlange/coderetreat.github.io,svenlange/coderetreat.github.io,svenlange/coderetreat.github.io,coderetreat/coderetreat.github.io,coderetreat/coderetreat.github.io,coderetreat/coderetreat.github.io,svenlange/coderetreat.github.io