Organize examples from guides they come from.
Adding first examples from Rust By Example while working through them.
Examples of operators and print statements.
Variable examples.
Mutable variable example.
Scope example is pretty straightforward.  Yay for scope!
Types are basic, note some unused variable warnings here were not surpressed.
Add .gitignore
Type casting examples
The constraint stuff is interesting as it infers the type of other variables from how it was used.
Pretty slick type inference example using vectors.
The type alias examples, which aren't immediately obviously super useful.