Add application configuration based on build environment

[thomasthiebaud]

This is a PR related to this issue #160

The main idea is to define an alias into webpack.config.js which pointed to the right config file.

It is then as simple as

import config from `config`
config.my_variable

to access the variable

[codecov-io]

Codecov Report

Merging #1053 into master will increase coverage by 1.55%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1053      +/-   ##
==========================================
+ Coverage   72.72%   74.28%   +1.55%     
==========================================
  Files          12       15       +3     
  Lines          66       70       +4     
==========================================
+ Hits           48       52       +4     
  Misses         18       18

Impacted Files	Coverage Δ
src/config/test.js	100% <100%> (ø)
src/config/development.js	100% <100%> (ø)
src/routes/Home/components/HomeView.js	100% <100%> (ø)	⬆️
src/config/production.js	100% <100%> (ø)

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[thomasthiebaud]

Does someone checked this PR ?

[dvdzkwsk]

@thomasthiebaud I'm just getting back into the swing of this project. I've glanced at it, and appreciate the contribution, but it may take me a day or two to come back to considering it more thoroughly. Sorry for the delay!

[thomasthiebaud]

I just rebased this PR, so it is up-to-date

[kbariotis]

Hello there @thomasthiebaud. Using the alias command means that the imported object will be included as is in the generated assets. Isn't this a problem because even the values that are not being used will be exposed to the consumer.

I am using DefinePlugin to expose environment based configuration to my app, which is being evaluated in compile time and exposes only the required values. Furthermore, I am defining feature toggles (simple booleans) on my configurations where if the toggle is false, UglifyJS will drop the dead code. Neat feature!

Would you consider a DefinePlugin based solution?