Name the app :dotenv, not :dotenv_elixir

The name of the repo is sufficient to identify it as an Elixir project,
but you should be able to use it as :dotenv in your mix.exs
Update elixir dependency to accept 0.15.0
Merge pull request #6 from lsimoneau/elixir-0.15

Update elixir dependency to 0.15.0
Merge pull request #5 from lsimoneau/rename-app

Name the app :dotenv, not :dotenv_elixir
Document public functions, add typespec, make private functions private
Merge pull request #7 from lsimoneau/documentation

Document public functions, add typespec, make private functions private
Simplify load/1 a little bit

* Use the pipeline to eliminate a temporary variable
* Hashdict.put serves the same purpose as merging a new Dict with only
  the desired values
Provide basic installation and usage instructions
Merge pull request #8 from lsimoneau/readme

README
Add MIT license
Add license information to hex project metadata
Merge pull request #10 from lsimoneau/license

Add MIT license
Touchup to the README
Specify links as a map in mix.exs