Update deprecation policy (#667)

* Updated deprecation policy

* drop "do our best to"

* Update `index.rst`

README.md

@@ -62,7 +62,7 @@ For information on installing from source, running CKT in a container, and platf
 
 ### Deprecation Policy
 
-This project is meant to evolve rapidly and, as such, does not follow [Qiskit's deprecation policy](https://github.com/Qiskit/qiskit/blob/main/DEPRECATION.md).  We may occasionally make breaking changes in order to improve the user experience.  When possible, we will keep old interfaces and mark them as deprecated, as long as they can co-exist with the new ones.  Each substantial improvement, breaking change, or deprecation will be documented in the [release notes](https://qiskit-extensions.github.io/circuit-knitting-toolbox/release-notes.html).
+We follow [semantic versioning](https://semver.org/) and are guided by the principles in [Qiskit's deprecation policy](https://github.com/Qiskit/qiskit/blob/main/DEPRECATION.md).  We may occasionally make breaking changes in order to improve the user experience.  When possible, we will keep old interfaces and mark them as deprecated, as long as they can co-exist with the new ones.  Each substantial improvement, breaking change, or deprecation will be documented in the [release notes](https://qiskit-extensions.github.io/circuit-knitting-toolbox/release-notes.html).
 
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docs/index.rst

@@ -14,7 +14,7 @@ The toolbox currently contains the following tools:
 
 For a more detailed discussion on circuit cutting, check out our `technical guide <./circuit_cutting/explanation/index.rst#overview-of-circuit-cutting>`__.
 
-This project is meant to evolve rapidly and, as such, does not follow `Qiskit's deprecation policy <https://github.com/Qiskit/qiskit/blob/main/DEPRECATION.md>`__.  We may occasionally make breaking changes in order to improve the user experience.  When possible, we will keep old interfaces and mark them as deprecated, as long as they can co-exist with the new ones.  Each substantial improvement, breaking change, or deprecation will be documented in the :ref:`release notes`.
+We follow `semantic versioning <https://semver.org/>`__ and are guided by the principles in  `Qiskit's deprecation policy <https://github.com/Qiskit/qiskit/blob/main/DEPRECATION.md>`__.  We may occasionally make breaking changes in order to improve the user experience.  When possible, we will keep old interfaces and mark them as deprecated, as long as they can co-exist with the new ones.  Each substantial improvement, breaking change, or deprecation will be documented in the :ref:`release notes`.
 
 Citing this project
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