Mention maps in crash-course
Remove outdated blog posts

* Get rid of the What's new in Elixir series (which is no longer maintained)
* Remove blog posts that feature records or have old/outdated code samples
Cut the gibberish in the introduction
Let's talk about the tooling too
Have a specific section for remote shells
Add img.no-border back
Start getting started guide rewrite
Add chapter on case, cond and if
Add binaries, strings and char lists chapter
Move iodata and char_data footnote to its own chapter
Keywords, maps and dicts
Expand structure for next chapters
Modules
Recursion
Module attributes
Add enumerables and streams, more progress on IO
Missing IO chapter
Talk about processes
Time to talk about IO
Add remaining chapters layout