docs/: Add help for contributors and a code of conduct for project

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

docs/CONTRIBUTING.md

@@ -0,0 +1,80 @@
+Contributing to sysklogd
+========================
+
+We welcome any and all help in the form of bug reports, fixes, patches
+for new features, *preferably as GitHub pull requests*.  Other methods
+are of course also possible: emailing the maintainer a patch or even a
+raw file, or simply emailing a feature request or an alert of a problem.
+However, email questions/requests/alerts always risk memory exhaustion
+on the part of the maintainer(s).
+
+If you are unsure of what to do, or how to implement an idea or bug fix,
+open an issue with the title `"[RFC: Unsure if this is a bug ... ?"`,
+or similar, so we can discuss it.  Talking about the code first is the best
+way to get started before submitting a pull request.
+
+Either way, when sending an email, patch, or pull request, start by
+stating the version the change is made against, what it does, and most
+importanyl -- why.
+
+Please take care to ensure you follow the project *coding style* and the
+commit message format.  If you follow these recommendations you help the
+maintainer(s) and make it easier for them to include your code.
+
+
+Coding Style
+------------
+
+> **Tip:** Always submit code that follows the style of surrounding code!
+
+First of all, lines are allowed to be longer than 72 characters these
+days.  In fact, there exist no enforced maximum, but keeping it around
+100 chars is OK.
+
+The coding style itself is otherwise strictly Linux [KNF][].
+
+
+Commit Messages
+---------------
+
+Commit messages exist to track *why* a change was made.  Try to be as
+clear and concise as possible in your commit messages, and always, be
+proud of your work and set up a proper GIT identity for your commits:
+
+    git config --global user.name "Jane Doe"
+    git config --global user.email jane.doe@example.com
+
+Example commit message from the [Pro Git][gitbook] online book, notice
+how `git commit -s` is used to automatically add a `Signed-off-by`:
+
+    Brief, but clear and concise summary of changes
+    
+    More detailed explanatory text, if necessary.  Wrap it to about 72
+    characters or so.  In some contexts, the first line is treated as
+    the subject of an email and the rest of the text as the body.  The
+    blank line separating the ummary from the body is critical (unless
+    you omit the body entirely); tools like rebase can get confused if
+    you run the two together.
+    
+    Further paragraphs come after blank lines.
+    
+     - Bullet points are okay, too
+    
+     - Typically a hyphen or asterisk is used for the bullet, preceded
+       by a single space, with blank lines in between, but conventions
+       vary here
+    
+    Signed-off-by: Jane Doe <jane.doe@example.com>
+
+
+Code of Conduct
+---------------
+
+It is expected of everyone engaging in the project to, in the words of
+Bill & Ted; [be excellent to each other][conduct].
+
+
+[KNF]:      https://en.wikipedia.org/wiki/Kernel_Normal_Form
+[gitbook]:  https://git-scm.com/book/ch5-2.html
+[conduct]:  https://github.com/troglobit/sysklogd/blob/master/docs/CODE-OF-CONDUCT.md
+