Add a minimal README

README.md

+# KDTree implementations comparison
+
+This compares several implementations of `KDTree` against one made using Cython+.
+
+## Reproducing benchmarks on GNU/Linux
+
+> ⚠ Currently this project `make` targets have been written for GNU/Linux as it makes
+> uses of `taskset(1)` to set CPU affinity. You define CPU affinity under others OS
+> easily using the `OMP_NUM_THREADS` environment variable.
+
+You need to have [`conda`](https://docs.conda.io/en/latest/) installed on your system.
+
+Then simply clone the repository and `make`:
+
+```bash
+git clone https://lab.nexedi.com/jjerphan/kdtree.git
+cd kdtree
+make
+```
+
+PDF reports will be written in a subfolder in `results` whose names match: `<commit-hash>_analysis`
+
+## Running tests
+
+```python
+conda activate kdtree
+pip install pytest
+pytest tests
+```