feat(process): load ENV variables into process.env

[sgtcoolguy]

JIRA: https://jira.appcelerator.org/browse/TIMOB-27045

Description:

• write env.json file with ENV variables
• lazily load those values into process.env at runtime

[build]

	Warnings
⚠️	iphone/cli/commands/_build.js#L6462 - iphone/cli/commands/build.js line 6462 – 'out' is defined but never used. Allowed unused args must match /^.+/. (no-unused-vars)

	Messages
📖	✅ All tests are passing Nice one! All 1939 tests are passing. (There are 226 tests skipped)

Generated by 🚫 dangerJS against c1f6269

addressed feedback

[sgtcoolguy]

For QE testing:

run a build with something like:

MY_ENV_VAR=testing ti build -p ios

And an app.js with:

Ti.API.info(process.env.MY_ENV_VAR);

It should print out "testing" in the log.

[ssjsamir]

FR Passed Able to load ENV variables into process.env.

Test Steps:

1. Created a new Titanium application with the build from this PR
2. Added the following in to the app.js:
   Ti.API.info(process.env.MY_ENV_VAR);
3. Ran the following command:
   MY_ENV_VAR=testing ti build -p ios
4. Able to see the following in the console:
   [INFO] testing

Test Environment

iPhone 6S plus (12.2 Sim)
APPC CLI: 7.0.12-70X.4
Operating System Name: Mac OS Mojave
Operating System Version: 10.14.2
Node.js Version: 8.11.3
Xcode 10.2.1

[hansemannn]

I think this pull request broke incremental builds. Can someone confirm? I noticed full rebuilds on every incremental build since last week. It can also be #10805 but I think it worked fine with that one.