allow options to be a JSON object

[yorek]

This commit allows complex object to be passed as option in the URI connection string. For example it's now possibile to do something like:

const sequelize = new Sequelize('mssql://user:password@server.database.windows.net/database?options={"encrypt":true}&anotherOption=1');

so that it will be possible to correctly connect to an Azure SQL database, as encryption is required

[codecov]

Codecov Report

Merging #12404 into master will increase coverage by 6.15%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master   #12404      +/-   ##
==========================================
+ Coverage   90.28%   96.44%   +6.15%     
==========================================
  Files          92       95       +3     
  Lines        8968     9114     +146     
==========================================
+ Hits         8097     8790     +693     
+ Misses        871      324     -547     

Impacted Files	Coverage Δ
lib/sequelize.js	95.87% <100.00%> (+0.69%)	⬆️
lib/dialects/mssql/query-interface.js	100.00% <0.00%> (ø)
lib/dialects/mssql/connection-manager.js	87.17% <0.00%> (ø)
lib/dialects/mssql/index.js	100.00% <0.00%> (ø)
lib/model.js	96.62% <0.00%> (+0.06%)	⬆️
lib/dialects/abstract/query-generator.js	97.39% <0.00%> (+1.26%)	⬆️
...dialects/abstract/query-generator/helpers/quote.js	100.00% <0.00%> (+6.66%)	⬆️
lib/dialects/mssql/data-types.js	100.00% <0.00%> (+69.87%)	⬆️
lib/dialects/mssql/async-queue.js	100.00% <0.00%> (+76.47%)	⬆️
... and 2 more

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[sushantdhiman]

Need some unit tests

sequelize/test/unit/configuration.test.js

Line 58 in c6e4192

describe('Instantiation with a URL string', () => {

[yorek]

Need some unit tests

sequelize/test/unit/configuration.test.js

Line 58 in c6e4192

describe('Instantiation with a URL string', () => {

Added test but for some reason it fails when run against a specific postgres test configuration, with a weird "leak" error, while it works perfectly on all others. As I'm really new to Node, any help is more than welcome.

[sushantdhiman]

LGTM, in future we can accept more keys for this sort of expansion other than options

[yorek]

Should I port this also to v5? My understanding is that the master is the latest (v6) version, right?

[sushantdhiman]

Yes, you may open a PR for v5 branch