Diagrams backend

[Leandro Damascena]

In this release it can export diagram using processes to instance a "ephemeral" file and get output. It work now and is a good approach, but we might have problem with heavy use. I think we should to think in a simple diagrams refactor to export "graphivz code" and run dot locally. I'll try to add a PR with this new implementation.

Code exported using diagrams (without render)
digraph "AWS VPC vpc-9cd235f5 Resources - Region af-south-1" {
graph [fontcolor="#2D3436" fontname="Sans-Serif" fontsize=15 label="AWS VPC vpc-9cd235f5 Resources - Region af-south-1" nodesep=2.0 pad=2.0 rankdir=TB ranksep=1.0 splines=curved]
node [fixedsize=true fontcolor="#2D3436" fontname="Sans-Serif" fontsize=13 height=1.4 imagescale=true labelloc=b shape=box style=rounded width=1.4]
edge [color="#7B8894"]
da94eca03d184e9c9d7034457f63a783 [label="vpc-9cd235f5" height=1.9 image="/tmp//aws/network\vpc.png" shape=none]
f666a65b5a7a4a168f4019bd88325218 [label="igw-a1d136c8" height=1.9 image="/tmp//aws/network\internet-gateway.png" shape=none]
b21c0245db4d447d84cb98b96e0bfa5a [label="acl-42d0372b" height=1.9 image="/tmp//aws/network\nacl.png" shape=none]
"097a523aaf614e419d29d6d1013d8159" [label="rtb-f4d2359d" height=1.9 image="/tmp//aws/network\route-table.png" shape=none]
"88ace327129749f6ab56cdf9cc11cba3" [label="Public subnets: subnet-04d0376d, subnet-e7d7f7ad, subnet-f8595880" height=1.9 image="/tmp//aws/network\public-subnet.png" shape=none]
"88ace327129749f6ab56cdf9cc11cba3" -> da94eca03d184e9c9d7034457f63a783 [dir=forward fontcolor="#2D3436" fontname="Sans-Serif" fontsize=13]
f666a65b5a7a4a168f4019bd88325218 -> da94eca03d184e9c9d7034457f63a783 [dir=forward fontcolor="#2D3436" fontname="Sans-Serif" fontsize=13]
b21c0245db4d447d84cb98b96e0bfa5a -> "88ace327129749f6ab56cdf9cc11cba3" [dir=forward fontcolor="#2D3436" fontname="Sans-Serif" fontsize=13]
"097a523aaf614e419d29d6d1013d8159" -> da94eca03d184e9c9d7034457f63a783 [dir=forward fontcolor="#2D3436" fontname="Sans-Serif" fontsize=13]
}