Remove suggestion that CGO isn't always needed (mattn#1290)

Fixes mattn#855

Author: samjewell

README.md

@@ -70,7 +70,6 @@ This package can be installed with the `go get` command:
 
 _go-sqlite3_ is *cgo* package.
 If you want to build your app using go-sqlite3, you need gcc.
-However, after you have built and installed _go-sqlite3_ with `go install github.com/mattn/go-sqlite3` (which requires gcc), you can build your app without relying on gcc in future.
 
 ***Important: because this is a `CGO` enabled package, you are required to set the environment variable `CGO_ENABLED=1` and have a `gcc` compiler present within your path.***