Fixes 65851432_about_blocks_master

* I learned that blocks can be described with curly brackets {} and do/end blocks
* I learned that blocks can take arguments
* I learned methods can call yield a lot of times
* Methods know if they have been called with a block
* Blocks can affect variables that they call
* Blocks can be assigned to variables
* Blocks can take an explicit block argument

[#65851432]