fix(typo): wiklink => wikilink (#39)

I copied the code from the README to start a project using this,
and ran into an issue due to the example code
referencing the package as `wiklink` rather than `wikilink`.

Did a find & replace in the project for `wiklink`,
replacing it with `wikilink`,
so the example code in the README should now be valid.

README.md

@@ -28,15 +28,15 @@ To use goldmark-wikilink, import the `wikilink` package.
 import "go.abhg.dev/goldmark/wikilink"
 ```
 
-Then include the `wiklink.Extender` in the list of extensions
+Then include the `wikilink.Extender` in the list of extensions
 that you build your [`goldmark.Markdown`] with.
 
   [`goldmark.Markdown`]: https://pkg.go.dev/github.com/yuin/goldmark#Markdown
 
 ```go
 goldmark.New(
   goldmark.WithExtensions(
-    &wiklink.Extender{},
+    &wikilink.Extender{},
   ),
   // ...
 )
@@ -61,7 +61,7 @@ to your `wikilink.Extender` when you install it.
 goldmark.New(
   goldmark.WithExtensions(
     // ...
-    &wiklink.Extender{
+    &wikilink.Extender{
       Resolver: myresolver,
     },
   ),

resolver.go

@@ -2,7 +2,7 @@ package wikilink
 
 import "path/filepath"
 
-// DefaultResolver is a minimal wiklink resolver that resolves wikilinks
+// DefaultResolver is a minimal wikilink resolver that resolves wikilinks
 // relative to the source page.
 //
 // It adds ".html" to the end of the target