DOC: Adapt the code of conduct removing "Enforcement Guidelines"

This commit removes the "Enforcement Guidelines" and intend to provide
more latitude in the handling of specific complaints by not creating the
expectations that we enforce behavior outside of the project.

Adaptation of the "Enforcement Guidelines" is aligned with the
"Before You Adopt Contributor Covenant" instructions available
since v2.1 (see [1]) and introduced following discussion in [2]:

> Before you decide to adopt Contributor Covenant, take the time to
> discuss enforcement with other trusted members of your community.
> Thoroughly read the Enforcement Guidelines section of the document.
> If the suggested actions and consequences don’t suit the context of
> your community, consider moving this section to another document (such
> as an FAQ or ‘How to Report’ page) and adapting it to your needs.

[1] EthicalSource/contributor_covenant@f46573395
    New recommendations - Enforcement Guidelines

[2] EthicalSource/contributor_covenant#910
    Consider breaking out the Enforcement Steps into a Separate Document

Co-authored-by: Andras Lasso <lasso@queensu.ca>
Co-authored-by: Jean-Christophe Fillion-Robin <jchris.fillion@kitware.com>
Co-authored-by: Lisa Avila <lisa.avila@kitware.com>
Co-authored-by: Sonia Pujol <spujol@bwh.harvard.edu>
Co-authored-by: Steve Pieper <pieper@isomics.com>
Co-authored-by: Yvette Fitzgerald <y.fitzgerald@kitware.com>

CODE_OF_CONDUCT.md

@@ -68,52 +68,6 @@ All complaints will be reviewed and investigated promptly and fairly.
 All community leaders are obligated to respect the privacy and security of the
 reporter of any incident.
 
-## Enforcement Guidelines
-
-Community leaders will follow these Community Impact Guidelines in determining
-the consequences for any action they deem in violation of this Code of Conduct:
-
-### 1. Correction
-
-**Community Impact**: Use of inappropriate language or other behavior deemed
-unprofessional or unwelcome in the community.
-
-**Consequence**: A private, written warning from community leaders, providing
-clarity around the nature of the violation and an explanation of why the
-behavior was inappropriate. A public apology may be requested.
-
-### 2. Warning
-
-**Community Impact**: A violation through a single incident or series of
-actions.
-
-**Consequence**: A warning with consequences for continued behavior. No
-interaction with the people involved, including unsolicited interaction with
-those enforcing the Code of Conduct, for a specified period of time. This
-includes avoiding interactions in community spaces as well as external channels
-like social media. Violating these terms may lead to a temporary or permanent
-ban.
-
-### 3. Temporary Ban
-
-**Community Impact**: A serious violation of community standards, including
-sustained inappropriate behavior.
-
-**Consequence**: A temporary ban from any sort of interaction or public
-communication with the community for a specified period of time. No public or
-private interaction with the people involved, including unsolicited interaction
-with those enforcing the Code of Conduct, is allowed during this period.
-Violating these terms may lead to a permanent ban.
-
-### 4. Permanent Ban
-
-**Community Impact**: Demonstrating a pattern of violation of community
-standards, including sustained inappropriate behavior, harassment of an
-individual, or aggression toward or disparagement of classes of individuals.
-
-**Consequence**: A permanent ban from any sort of public interaction within the
-community.
-
 ## Attribution
 
 This Code of Conduct is adapted from the [Contributor Covenant][homepage],