Divide MBs by 10^6 and round the result

[wowshakhov]

closes #1382

[bwsw]

@wowshakhov please check build fail status by Travis.

[coveralls]

Pull Request Test Coverage Report for Build 1909

• 6 of 9 (66.67%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.009%) to 53.787%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/app/shared/services/utils/utils.service.ts	0	1	0.0%
src/app/shared/pipes/convert-to-mb.pipe.ts	5	7	71.43%
<!--	Total:	6	9	66.67%	-->

Totals
Change from base Build 1904:	0.009%
Covered Lines:	9804
Relevant Lines:	16198

---

💛 - Coveralls