[docs] Replace Markdown in HTML with pure HTML

Author: salkinium

docs/index.md.in

@@ -1,8 +1,8 @@
 <!-- This file is generated by tools/scripts/synchronize_docs.py! -->
 # modm: a barebone embedded library generator
-<center>
-![](images/logo.svg)
-</center>
+
+<img src="images/logo.svg" style="display: block; margin: auto;"/>
+
 {{content}}
 
 ### Examples

docs/mkdocs.yml

@@ -74,7 +74,6 @@ markdown_extensions:
   - pymdownx.tasklist:
       custom_checkbox: true
   - pymdownx.tilde
-  - md_in_html
 
 nav:
   - Home:

docs/src/how-modm-works.md

@@ -13,9 +13,7 @@ specifically for your targets and needs and generate a custom library.
 You can generate more than just code, in this example, lbuild also generates a
 build system which then compiles and links the application into a executable.
 
-<center>
-![](images/system-overview.svg)
-</center>
+<img src="../images/system-overview.svg" style="display: block; margin: auto;"/>
 
 We've also put a lot of thought into modm-devices, about what data to extract,
 how to format and store it. We automated the entire process to get the high
@@ -34,7 +32,7 @@ by looking at the dependency graph before, or by inspecting the generated code
 after calling lbuild, and gives you the opportunity to only use the parts of
 modm you really like.
 
-![](images/uart-dep-graph.svg)
+<img src="../images/uart-dep-graph.svg" style="display: block; margin: auto;"/>
 
 A lbuild module is just a few lines of Python code. Here we can see the code for
 the `modm:platform:uart` module from the example above. It declares its name,