Added support for the --target flag

[AndyBitz]

This will add support for the --target flag as soon as it launches.

Example output:

• date-test $ cat now.json 
{
 "version": 2,
 "builds": [
  { "src": "date.js", "use": "@now/node" }
 ],
 "alias": "now-test-alias-for-production-00000000001.now.sh"
}
• date-test $ node ../now-cli/dist/index.js
> Deploying ~/projects/zeit/date-test under so-noice-right
> Using project date-test
> Synced 1 file (140B) [1s]
> https://date-test-kngwl37q2.now.sh [v2] [in clipboard] [3s]
┌ date.js        Ready               [21s]
└── λ date.js (1.97KB) [bru1]
> Success! Your deployment is now available on artzbitz-date-test.so-noice-right.now.sh [1m]
• date-test $ node ../now-cli/dist/index.js --target production
> Deploying ~/projects/zeit/date-test under so-noice-right
> Using project date-test
> https://date-test-gh3mce6d0.now.sh [v2] [in clipboard] [4s]
┌ date.js        Ready               [22s]
└── λ date.js (1.97KB) [bru1]
> Success! Your deployment is now available on now-test-alias-for-production-00000000001.now.sh and artzbitz-date-test.so-noice-right.now.sh [28s]
• date-test $ 

[codecov-io]

Codecov Report

Merging #1893 into canary will decrease coverage by 0.31%.
The diff coverage is 0%.

@@            Coverage Diff            @@
##           canary   #1893      +/-   ##
=========================================
- Coverage    6.64%   6.33%   -0.32%     
=========================================
  Files          93      91       -2     
  Lines        4048    4058      +10     
=========================================
- Hits          269     257      -12     
- Misses       3779    3801      +22

Impacted Files	Coverage Δ
src/commands/deploy/args.js	0% <ø> (ø)	⬆️
src/commands/deploy/latest.js	0% <0%> (ø)	⬆️
src/util/index.js	0% <0%> (ø)	⬆️
src/util/get-project-name.js	90.9% <0%> (-9.1%)	⬇️
src/util/get-files.js	91.53% <0%> (-8.47%)	⬇️

---

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