Prepare for v0.7.0 release (unitaryfund#627)

* update changelog for v.0.7

* more updates to changelog for v.0.7

CHANGELOG.md

@@ -8,19 +8,36 @@
 % # " - [Bug Fix]"
 % # " - Fix the bug."
 
-## Version 0.7.0 (In Development)
+## Version 0.7.0 (April 6th, 2021)
+
+### Summary
+
+This release focuses on contributions from the community.
+Many thanks @yhindi for adding a method to parametrically scale noise in circuit, to @aaron-robertson and @pchung39 for adding Qiskit executors with depolarizing noise to the utils,
+to @purva-thakre for several bug fixes and improvements. Thanks also to @BobinMathew and @marwahaha for typo corrections.
+
 
 ### All Changes
 
+- Pin `docutils` version to solve CI issues (@purva-thakre, gh-626)
 - Add qiskit executor example for exact density matrix simulation with depolarizing noise (@aaron-robertson, gh-574)
-- Replace Qiskit utils with Qiskit executors from docs  (@pchung39, @aaron-robertson, gh-584)
+- Replace Qiskit utils with Qiskit executors from docs (@pchung39, @aaron-robertson, gh-584)
+- Change custom depolarizing channel in PEC (@purva-thakre, gh-615)
+- Document codecov fetch depth change and increase codecov action version (@grmlarose, gh-618)
+- Fix spelling typo (@marwahaha, gh-616)
+- Add link for MEP (@purva-thakre, gh-610)
+- Correct a typo in the readme (@BobinMathew, gh-609)
 - Add ``represent_operations_in_circuit_...`` functions for PEC (@andreamari, gh-515)
 - Add qiskit and cirq executor examples gifs to readme (@nathanshammah, gh-587)
-- Fix mitiq.about() qiskit version (@aaron-robertson, gh-595)
+- Add parametrized scaling (@yhindyYousef, gh-411)
+- Fix mitiq.about() qiskit version (@aaron-robertson, gh-598)
 - Fix typo in ZNE documentation (@purva-thakre, gh-602)
-- [Bug Fix] Examples (notebooks) in the online documentation now have output code cells (@andreamari, gh-576)
-
-
+- Add minimal section on PEC to documentation (@nathanshammah @andreamari, gh-564)
+- Various improvements to CI and testing (@rmlarose, gh-583)
+- Corrects typo in docs of error mitigation guide (@purva-thakre, gh-585)
+- Remove factory equality and fix bug in `PolyExpFactory.extrapolate` (@rmlarose, gh-580)
+- [Bug Fix] Examples (notebooks) in the online documentation now have output code cells (@Aaron-Robertson, gh-576)
+- Update version to dev (@andreamari, gh-572)
 
 - Change custom depolarizing channel in PEC test (@purva-thakre, gh-615)