OSS Support Grant: Milestone 2 - Add methods to inspect account storage

[MaxStalker]

This PR adds multiple new methods to query storage

• Documentation added

For contributor use:

• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[github-actions]

Dependency Testbed

• Flow CLI: 0.48.0
• FCL: ^1.3.2

Release Version

The package containing these changes will be released with version 0.4.0

[github-actions]

Coverage report

St.❔	Category	Percentage	Covered / Total
🟢	Statements	92.44% (-0.24% 🔻)	624/675
🟡	Branches	76.42% (-0.46% 🔻)	188/246
🟢	Functions	93.33% (+0.29% 🔼)	126/135
🟢	Lines	92.88% (-0.32% 🔻)	600/646

Show new covered files 🐣

St.❔	File	Statements	Branches	Functions	Lines
🟢	storage.js	90.91%	66.67%	93.33%	90.91%

Show files with reduced coverage 🔻

St.❔	File	Statements	Branches	Functions	Lines
🟢	utils.js	88.57% (-5.87% 🔻)	78.26% (+0.48% 🔼)	100%	90% (-10% 🔻)

Test suite run success

111 tests passing in 15 suites.

Report generated by 🧪jest coverage report action from 016db8d