Updated code style

CODE_STYLE.md

@@ -4,7 +4,7 @@ This document is only meant to teach you the code style used in this project and
 
 ## Tabs vs Spaces
 
-Use **tabs to indent** and **spaces for alignment** only:
+Use tabs for indentation and spaces for alignment:
 
 ```go
 type AnimeTitle struct {
@@ -61,7 +61,7 @@ func() {
 
 Variables are written in `camelCase` and should clearly state what they contain, preferably with no abbreviations. Common short names like `id` and `url` are allowed.
 
-Iterator variables in loops are an exception to this rule and can be 1-letter, non-significant variable names, usually `i` and `j`.
+Iterator variables in loops are an exception to this rule and can be 1-letter, non-significant variable names, usually `i` and `j`. `index` is also quite common.
 
 ## Early returns
 
@@ -89,7 +89,11 @@ func DoSomething(a string, b string) {
 }
 ```
 
-## Private fields at the end
+## Types at the top
+
+`type` definitions should be placed at the very top of your files. Variables, constants, interface implementation assertions and the `package` statement are the only constructs allowed above `type` definitions.
+
+## Private fields at the end of a struct
 
 This is not an absolute rule but try to keep private fields at the end of a struct.
 
@@ -106,3 +110,11 @@ type MyType struct {
 ## Package names
 
 Package names should be short lowercase identifiers and tests should be written using the black box pattern. Black box testing can be enabled by adding the suffix `_test` to the package names in `*_test.go` files. It will enable you to test your library like it would be used by another developer, without internal access to private variables.
+
+## Use gofmt
+
+Your IDE should automatically call `gofmt` to format your code every time you save the file.
+
+## Code editor
+
+It is highly recommended to use [Visual Studio Code](https://code.visualstudio.com/) as it has an excellent Go plugin and the repository includes workspace settings to get you started quickly.