demos: Move benchmarks to maint directory

diff --git a/demos/benchmark/benchmark.py b/maint/benchmark/benchmark.py
similarity index 100%
rename from demos/benchmark/benchmark.py
rename to maint/benchmark/benchmark.py

diff --git a/demos/benchmark/chunk_benchmark.py b/maint/benchmark/chunk_benchmark.py
similarity index 100%
rename from demos/benchmark/chunk_benchmark.py
rename to maint/benchmark/chunk_benchmark.py

diff --git a/demos/benchmark/gen_benchmark.py b/maint/benchmark/gen_benchmark.py
similarity index 100%
rename from demos/benchmark/gen_benchmark.py
rename to maint/benchmark/gen_benchmark.py

diff --git a/demos/benchmark/stack_context_benchmark.py b/maint/benchmark/stack_context_benchmark.py
similarity index 100%
rename from demos/benchmark/stack_context_benchmark.py
rename to maint/benchmark/stack_context_benchmark.py

diff --git a/demos/benchmark/template_benchmark.py b/maint/benchmark/template_benchmark.py
similarity index 100%
rename from demos/benchmark/template_benchmark.py
rename to maint/benchmark/template_benchmark.py