Allow multiple before_deploy blocks to be defined

[schneems]

The current behavior of calling before_deploy will replace the existing block. This new behavior allows the end developer more control so they can fire multiple disk modifications if desired.

I'm also deprecating calling before_deploy as a mechanism to delete/replace any previously set block. In the future I'll make the default behavior of calling the block multiple times match before_deploy(:append)

[Malax]

Do you have a real-world example where this feature is useful? I assume you implemented this because you had a use for it, I'm curious. :)

[schneems]

Do you have a real-world example where this feature is useful? I assume you implemented this because you had a use for it, I'm curious. :)

It was originally requested by @dzuelke. One possible use case:

• You need to add some helper file to all the tests in a file, so you define a before_deploy on them in some sort of a method to reduce duplication
• Later you realize several of them need further modification, but not all of them. Without this it's possible but tricky to make that work. With this you can tack on additional file modifications without worry for over-writing existing ones.