Fix unicorn-emulate cmd

[theguy147]

Fix unicorn-emulate cmd

Description/Motivation/Screenshots

This PR is part of #693 and covers the following points:

• Fix emulating the wrong number of instructions for even numbers
• Update docs for cmd (incl Screenshot)
• Fix alignment of registers in output
• Fix address parsing of cmd
• Update test to check for failed emulations and count the number of emulated instructions

Here some before/after screenshots:

Before

After

In the future it might even be cool to print the registers in GEFs standard way (incl marking tainted registers with color) but this PR was more about fixing the broken parts of the command.

How Has This Been Tested?

Architecture	Yes/No	Comments
x86-32	✔️
x86-64	✔️
ARM	✖️
AARCH64	✖️
MIPS	✖️
POWERPC	✖️
SPARC	✖️
RISC-V	✖️
make test	✔️

Checklist

• My PR was done against the dev branch, not master.
• My code follows the code style of this project.
• My change includes a change to the documentation, if required.
• My change adds tests as appropriate.
• I have read and agree to the CONTRIBUTING document.

[hugsy]

👍
Maybe just squash before merge.