sources arg ignored in load_environ

[rsgalloway]

it looks like the sources arg is being ignored/clobbered in load_environ and it gets redefined here.

in addition, executing a .env file on the command line is not inclusive to that single .env stack file if the basename is also found in the path. for example, executing a local ./test.env file will also source any other other test.env files found in the path.

[rsgalloway]

removing the sources arg for now. if we need to load an env from a list of sources we can add a new function for that.