Added --plain --no-chars and --no-position toggles

[mkatychev]

New flags added:

OPTIONS:
    -p, --plain                 Display output with --no-chars, --no-position, and
                                --border=none.
    -C, --no-chars              Whether to display the character table on the right.
    -P, --no-position           Whether to display the position indicator on the left.

Motivation was mainly for diffing two separate binary files, borders could be removed but char table and position still created a lot of noise.

Output example:

[sharkdp]

Before I proceed to review this: how does this integrate with what is being proposed in #149?

[mkatychev]

Before I proceed to review this: how does this integrate with what is being proposed in #149?

This PR does not toggle separators or modify existing border behaviour, it allows the toggling of the character table (on the right) and the hex position (on the right).

• This PR allows one to disable the 1st and/or 3rd column
• --plain disables both and applies the existing --border=none flag as a convenience flag

[sharkdp]

Nice! Thank you. Mainly have some questions regrading the command-line interface (option names)

[sharkdp]

Thank you for the updates!