(Fix) Statistics new metrics: ongoing, future, past crowdsales

[vbaranov]

Closes #620

Token Wizard statistics new metrics:

• future crowdsales amount
• past crowdsales amount
• ongoing crowldsales amount

Also,

• Only sane crowdsales are accounted
• % of finalized crowdsales is accounted from past crowdsales

[coveralls]

Pull Request Test Coverage Report for Build 2219

• 0 of 86 (0.0%) changed or added relevant lines in 2 files are covered.
• 5 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.3%) to 21.85%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/utils/blockchainHelpers.js	0	33	0.0%
src/components/stats/index.js	0	53	0.0%
<!--	Total:	0	86	0.0%	-->

Files with Coverage Reduction	New Missed Lines	%
src/utils/blockchainHelpers.js	1	8.74%
src/components/stats/index.js	4	0.0%
<!--	Total:	5		-->

Totals
Change from base Build 2214:	-0.3%
Covered Lines:	651
Relevant Lines:	2605

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💛 - Coveralls