[libgda] Add contribution guide

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit 148daffd7ff5ed8121a3aebf505d2b97337845b1
Author: Daniel Espinosa Ortiz <esodan gmail com>
Date:   Tue Dec 11 18:50:49 2018 +0000

    Add contribution guide

 CONTRIBUTING.md | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)
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diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
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index 000000000..bcfd6433a
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+CONTRIBUTOR COVENANT CODE OF CONDUCT
+Our Pledge
+In the interest of fostering an open and welcoming environment, we as contributors and maintainers pledge to 
making participation in our project and our community a harassment-free experience for everyone, regardless 
of age, body size, disability, ethnicity, sex characteristics, gender identity and expression, level of 
experience, education, socio-economic status, nationality, personal appearance, race, religion, or sexual 
identity and orientation.
+
+Our Standards
+Examples of behavior that contributes to creating a positive environment include:
+
+Using welcoming and inclusive language
+Being respectful of differing viewpoints and experiences
+Gracefully accepting constructive criticism
+Focusing on what is best for the community
+Showing empathy towards other community members
+Examples of unacceptable behavior by participants include:
+
+The use of sexualized language or imagery and unwelcome sexual attention or advances
+Trolling, insulting/derogatory comments, and personal or political attacks
+Public or private harassment
+Publishing others’ private information, such as a physical or electronic address, without explicit permission
+Other conduct which could reasonably be considered inappropriate in a professional setting
+Our Responsibilities
+Project maintainers are responsible for clarifying the standards of acceptable behavior and are expected to 
take appropriate and fair corrective action in response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or reject comments, commits, code, 
wiki edits, issues, and other contributions that are not aligned to this Code of Conduct, or to ban 
temporarily or permanently any contributor for other behaviors that they deem inappropriate, threatening, 
offensive, or harmful.
+
+Scope
+This Code of Conduct applies both within project spaces and in public spaces when an individual is 
representing the project or its community. Examples of representing a project or community include using an 
official project e-mail address, posting via an official social media account, or acting as an appointed 
representative at an online or offline event. Representation of a project may be further defined and 
clarified by project maintainers.
+
+Enforcement
+Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by contacting the 
project team at [INSERT EMAIL ADDRESS]. All complaints will be reviewed and investigated and will result in a 
response that is deemed necessary and appropriate to the circumstances. The project team is obligated to 
maintain confidentiality with regard to the reporter of an incident. Further details of specific enforcement 
policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good faith may face temporary or 
permanent repercussions as determined by other members of the project’s leadership.
+
+Attribution
+This Code of Conduct is adapted from the Contributor Covenant, version 1.4, available at 
https://www.contributor-covenant.org/version/1/4/code-of-conduct.html
+
+For answers to common questions about this code of conduct, see https://www.contributor-covenant.org/faq
\ No newline at end of file