GH-621: Added the required Git version to prerequisites.
GH-621: Added the required Git version to prerequisites.

It should be 2.11.0 or higher. Otherwise `--porcelain=2` cannot be
used to parse the Git status output from the command line.

Signed-off-by: Akos Kitta <5adc53eb8928d8424ddf49bf102dba40aa33cffe@gmail.com>

hexa00/theia,hexa00/theia,epatpol/theia-1,epatpol/theia-1,epatpol/theia-1