docs: add installation instruction

README.md

@@ -1,6 +1,29 @@
 # Oxford Spires Dataset
 This repository contains scripts that are used to evaluate Lidar/Visual SLAM on the Oxford Spires Dataset.
 
+## Installation
+### oxford_spires_utils (Python)
+```bash
+pip install -e .
+```
+
+### octomap_utils (C++)
+Install octomap to your system
+```bash
+git clone https://github.com/OctoMap/octomap.git && cd octomap
+mkdir build && cd build
+cmake ..
+make
+sudo make install
+```
+Then install the sripts in Spires.
+```bash
+cd <oxford_spires_dataset>/octomap_utils
+mkdir build && cd build
+cmake ..
+make
+```
+
 ## Contributing
 Please refer to Angular's guide for contributing(https://github.com/angular/angular/blob/22b96b96902e1a42ee8c5e807720424abad3082a/CONTRIBUTING.md).