add Request.Insecure option
go fmt
Fix warning due to "HaveOccured" being deprecated

```
WARNING: The HaveOccured matcher is deprecated!
We've corrected the spelling of "HaveOccured" to "HaveOccurred".
Update your package by running "gofmt -r 'HaveOccured() -> HaveOccurred()' -w *.go".
```
add test and make sure that one Insecure request doesn't cause all subsequent requests to be insecure as well
remove unused + unexported concat function
Add transport instance per request to avoid concurreny problems
Add transport instance per request to avoid concurreny problems
Merge pull request #1 from marcosnils/DoInsecure

Do insecure
use one transport per Request struct
add test for local transport
Merge pull request #36 from ryansb/DoInsecure

Add a method to bypass TLS verification