remove wiki section on big docs, cascadia is now almost as fast as workarounds

Author: mna

doc/tips.md

@@ -1,28 +1,5 @@
 # Tips and tricks
 
-## Manipulate Big Documents
-
-Some CSS selectors are inherently slower than others, and when manipulating big documents (e.g. tables with thousands of rows), the performance may suffer. In particular, pseudo-classes such as `:nth-child` are slow, and while they are handy when manipulating smaller documents, they can be painful for bigger ones.
-
-In those cases, it can be order of magnitudes faster to use a simpler CSS selector and use goquery methods to do the finer-grained filtering.
-
-For example:
-
-```
-doc, err := goquery.NewDocumentFromReader(bigDocument)
-if err != nil {
-    log.Fatal(err)
-}
-
-// this could be much slower...
-sel := doc.Find("#bigtable tr:nth-child(1) td")
-
-// than this:
-sel := doc.Find("#bigtable tr").First().Find("td")
-```
-
-Other indexes in an `:nth-child(x)` can be translated to `sel.Eq(x)`.
-
 ## Handle Non-UTF8 html Pages
 
 The `go.net/html` package used by `goquery` requires that the html document is UTF-8 encoded. When you know the encoding of the html page is not UTF-8, you can use the `iconv` package to convert it to UTF-8 (there are various implementation of the `iconv` API, see [godoc.org][iconv] for other options):