Write slides about merge with conflict

shell/complex-merge

@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+
+DIR="$(dirname "$(readlink -f "$0")")"
+cd /tmp/demo
+git switch master > /dev/null
+git branch dog > /dev/null
+cp "${DIR}/../code-examples/python-cat.py" greeting.py > /dev/null
+git add greeting.py > /dev/null
+git commit -m "Makes a cat say Meow" > /dev/null
+git switch dog > /dev/null
+cp "${DIR}/../code-examples/python-dog.py" greeting.py > /dev/null
+git add greeting.py > /dev/null
+git commit -m "Makes a dog say Woof" > /dev/null
+git switch master > /dev/null
+echo "  # Make changes to 2 branches in the same place #"
+echo '$ git switch master'
+echo '$ git log --oneline --all --graph'
+git -c color.ui=always log --oneline --all --graph --decorate=short
+echo '$ git merge dog'
+git merge dog --no-edit