Wyatt/3882 log subscription

[spacesailor24]

Description

Fix default value for fromBlock option for logs subscriptions (defaults to latest)

Fixes #3882

I did test that that options here looks like {fromBlock: 'latest'} when logs subscription is initialized via:

var subscription = web3.eth.subscribe('logs', 
    {fromBlock: `latest` }, // Or a specific block number 
    function(error, result){ ... }

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• I have selected the correct base branch.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• Any dependent changes have been merged and published in downstream modules.
• I ran npm run dtslint with success and extended the tests and types if necessary.
• I ran npm run test:unit with success.
• I ran npm run test:cov and my test cases cover all the lines and branches of the added code.
• I ran npm run build and tested dist/web3.min.js in a browser.
• I have tested my code on the live network.
• I have checked the Deploy Preview and it looks correct.
• I have updated the CHANGELOG.md file in the root folder.

[coveralls]

Pull Request Test Coverage Report for Build 510320721

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 17 unchanged lines in 2 files lost coverage.
• Overall coverage increased (+0.04%) to 76.269%

---

Files with Coverage Reduction	New Missed Lines	%
packages/web3-core-helpers/src/formatters.js	1	82.27%
packages/web3-core-helpers/lib/formatters.js	16	81.27%

Totals
Change from base Build 504724575:	0.04%
Covered Lines:	3171
Relevant Lines:	3943

---

💛 - Coveralls

[GregTheGreek]

can you update the documentation to acknowledge a default :)

[frankiebee]

update docs

[GregTheGreek]

🍻

She helped me come up with the docs update