Updated development docs accorging new requirements lists

Closes-Bug: 1259556
Change-Id: I278a1b154e0dfc60d71109c6caf824c2a2b0385c
Merge "Updated development docs accorging new requirements lists"
Fixed typo to make build good

Change-Id: Ifed0e5963e604ab26a9567ff3bb95d5052a57226
Decrease default number of vlans for neutron+vlan mode

Closes-bug: #1263957
Change-Id: I497542e7a3a225952fa4ac3d30b65192cee81243
Fix for external network gateway

Change-Id: I7565f6133fa5c22471a7047a4f6e029e00be10de
Closes-Bug: #1264107
Disable OpenStack logs in Fuel 4.0

This change is for stable/4.0 branch only.

Change-Id: Idf4301f683c177b266a5b94fe966ebf92b96b500
Closes-Bug: 1264080