docs: 2.2 release announcement updated

docs/blog/posts/2.2.0-released.md

@@ -21,7 +21,7 @@ significant changes introduced by the new version can be found in our
 
 <!-- more -->
 
-## C++20 modules
+## C++20 modules and project structure cleanup
 
 [GitHub Issue #7](https://github.com/mpusz/mp-units/issues/7) was our oldest open issue
 before this release. Not anymore. After 4.5 years, we finally closed it, even though
@@ -90,9 +90,46 @@ In version 2.2, the following headers have a new location or contents:
 | _mp-units/systems/angular/math.h_ | `mp_units.systems` | Trigonometric functions using `angular::radian` |
 | _mp-units/systems/si/chrono.h_    | `mp_units.systems` | `std::chrono` compatibility traits              |
 
+Benefiting from this opportunity, we also cleaned up core and systems definitions
+(:boom: **breaking change** :boom:).
+
+Regarding the library's core, we exposed only one header `framework.h` that exposes all of
+the library's framework so the user does not have to enumerate files like `unit.h`, `quantity.h`,
+and `quantity_point.h` anymore. Those headers are not gone, they were put to
+the `mp-units/framework` subheader. So they are still there if you really need them.
+
+Regarding the changes in systems definitions, we moved the wrapper header files with the entire
+system definition to the `mp-units/systems` subdirectory. Additionally, they now also include
+`framework.h`, so a system include is enough to use the library. Thanks to that our users don't
+have to write tedious code like the below anymore:
+
+=== "Now"
+
+    ```cpp
+    #include <mp-units/systems/cgs.h>
+    #include <mp-units/systems/international.h>
+    #include <mp-units/systems/isq.h>
+    #include <mp-units/systems/si.h>
+
+    // ...
+    ```
+
+=== "Before"
+
+    ```cpp
+    #include <mp-units/quantity_point.h>
+    #include <mp-units/systems/cgs/cgs.h>
+    #include <mp-units/systems/international/international.h>
+    #include <mp-units/systems/isq/isq.h>
+    #include <mp-units/systems/si/si.h>
+
+    // ...
+    ```
+
 Additionally, we merged all of the compatibility-related macros into one header file
-_mp-units/compat_macros.h_. This header file should be explicitly included before importing C++
-modules if we want to benefit from the [Wide Compatibility tools](../../users_guide/use_cases/wide_compatibility.md).
+`mp-units/compat_macros.h`. This header file should be explicitly included before importing C++
+modules if we want to benefit from the
+[Wide Compatibility tools](../../users_guide/use_cases/wide_compatibility.md).
 
 
 ## Better control over the library's API
@@ -383,13 +420,13 @@ Also, the header itself was split into smaller pieces that improve C++20 modules
 
 ## `ratio` made an implementation detail of the library
 
-We decided not to expose `ratio` and associated types in the public interface of the library
+We decided not to expose `ratio` and associated interfaces in the public part of the library
 (:boom: **breaking change** :boom:). Standardization of it could be problematic as we have
 [`std::ratio`](https://en.cppreference.com/w/cpp/numeric/ratio/ratio) already.
 
-Alternatively, we introduced a new helper called `mag_ratio` to provide the magnitude of the unit
-defined in terms of a rational conversion factor. Here is a comparison of the code with previous
-and current definitions:
+Alternatively, as in the public interface it was always only used with `mag`, we introduced a new
+helper called `mag_ratio` to provide the magnitude of the unit defined in terms of a rational
+conversion factor. Here is a comparison of the code with previous and current definitions:
 
 === "Now"