update installation instruction and add git as build dependency

[bokunodev]

update installation instruction and add git as build dependency

Changes to be committed: modified: README.md

[coveralls]

Pull Request Test Coverage Report for Build 3173070215

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-18.3%) to 53.933%

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Files with Coverage Reduction	New Missed Lines	%
connmgr/connmanager.go	2	86.79%
<!--	Total:	2

Totals
Change from base Build 3045304354:	-18.3%
Covered Lines:	25143
Relevant Lines:	46619

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💛 - Coveralls