title: Automatically define GOPATH on a per project basis
body: <p>For every project I create, I have to do <code>export GOPATH={path_to_project}</code> every time I cd into the project dir.  There has to be an easier way.  Isn't there some way I can create a .bashrc or .bash_profile file for a given directory to define the GOPATH for that project?</p>
  <p>For example, I have two go projects A and B. If I have a singular GOPATH that isn't redefined when I move between projects, then binaries for both projects will be stored in the same place.  More importantly, binaries for third party libraries will be stored in the same place, so I have no way of maintaining multiple versions of the same library on a per project basis.</p>
  <p>However, if I am able to define GOPATH on a per project basis, then all binaries and third party libraries are project dependent.  This seems to be the common way of handling package management in most other language environments (ruby rbenv, python vertiualenv, etc.)</p>