Revert "aded gradle wrapper, no need to preinstall it"

This reverts commit 135b7c3807f3964d27ad0ae244561976e6bf495a.
Revert "Removed comment line"

This reverts commit 107ce50a8d638d986e7a8c13c31f6f02c4c8a72f.
Revert "Introduction of gradle ph2"

This reverts commit 71c16e6f387e3a6fec1cfcd80eb40592705c502e.
Revert "Added gradle 2.1 as building script."

This reverts commit b17fa9008509407564eac5de48417287d0449b4c.