Prepare README and user guide

[kyasbal]

No description provided.

[kyasbal]

Fixing illustrations are not so complex. Feel free to point out anything if you find something to fix in images.

[kyasbal]

I added new images for query and the header.
I think it would be better to use animated GIF eventually, but I put 2 main screenshots on the top instead for a while.

[renamoo]

Maybe something like this to keep the header would be easier to see there is another option to get started, but it's nit, so leaving LGTM anyway.

## Get Started (Run from source)

<details>
<summary> Click to open steps to get started from source</summary>

[kyasbal]

Maybe something like this to keep the header would be easier to see there is another option to get started, but it's nit, so leaving LGTM anyway.

## Get Started (Run from source)

<details>
<summary> Click to open steps to get started from source</summary>

I agree with your opinion. I put the section header outside of the block.
The review become outdated. Please approve it again when you are free.

[RyuSA]

let me leave some comment!!

[kyasbal]

We can merge this. But I'll wait @RyuSA 's opinion for in case.

[RyuSA]

LGTM👍