Add README

README.md

+iris-atomic
+====
+
+Atomicity related verification based on Iris logic.
+
+Build
+--------
+
+1. `git clone` this repo
+2. `git submodule update --init` to fetch corresponding Iris library as a submodule
+3. `cd iris-coq; make; make install` to install Iris library (system globally). Or you can use `make userinstall` to install user globally.
+4. `cd ..; make` to compile this repo
+