unsecure-connection in README.md

[AF]

The documentation of unsecure-connection flag in README.md is missing.

I think it is sufficient to add a point in the Usage/Options section, for example

• -u --unsecure-connection: send framebuffer data over an unencrypted TCP-connection, resulting in more fps and less load on the reMarkable. See Unsecure Connection for installation instructions.

And a subsection Unsecure Connection in Requirements. I do not use apt, so I do not know for Ubuntu how is call the package name of netcat, which provides the command nc and which implementation do you want to use.

[Rien]

You are absolutely right!

I'll welcome a PR for this, but can look at this later myself if nobody has made one yet.

[Rien]

Closed by #52