activation script not set when using alt filename

[majidaldo]

if you put this in say _.yml

channels:
- conda-forge
name: _
dependencies: ['curl']
environment:
  VAR: val

conda dev env --file _.yml doesn't put the activation script; the env var is not set. Furthermore, conda complains about the environment section.

[prusse-martin]

2 things here:

1. conda dev env --file _.yml has an extra space, it should be conda devenv --file _.yml (I guess that was just a typo when creating this issue);
2. When the file has not the extension .devenv.yml conda-devenv no not process the file at all and just forwards it to conda. This is actually a recurrent problem (Don't require .devenv.yml extension with --file option (or document better). #90), probably we will just be better to just lift that especial case and hope for the best;