Add CONTRIBUTING.md and .github/PULL_REQUEST_TEMPLATE.md (#174)

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,13 @@
+## CSL Locales Pull Request Template
+
+You're about to create a pull request to the CSL locales repository.
+If you haven't done so already, see http://docs.citationstyles.org/en/stable/translating-locale-files.html for instructions on how to translate CSL locale files, and https://github.com/citation-style-language/styles/blob/master/CONTRIBUTING.md on how to submit your changes.
+In addition, please fill out the pull request template below.
+
+### Description
+
+Briefly describe the changes you're proposing.
+
+### Checklist
+
+- [ ] Check that you're listed as a `<translator>` in the `<info>` block at the beginning of the file.

CONTRIBUTING.md

@@ -0,0 +1,28 @@
+# Contributing to the CSL locale repository
+
+We welcome contributions to the Citation Style Language (CSL) locale files in this repository.
+
+The CSL locale files provide the standard translations for automatic localization of CSL styles.
+As such, the CSL locale files should generally contain the most commonly used translations for a given locale.
+Less common translations can be [provided in the individual CSL styles](http://docs.citationstyles.org/en/stable/specification.html#locale) that require them, which will overwrite the CSL locale file translations.
+
+Because each CSL locale file offers the standard translations for all CSL styles, changes should be made conservatively and carefully.
+We will often ask a second native speaker and/or past contributor to look over your proposed changes.
+
+## Licensing and crediting
+
+By creating a pull request, you agree to license your contributions under the [Creative Commons Attribution-ShareAlike 3.0 Unported license](http://creativecommons.org/licenses/by-sa/3.0/) license.
+
+In addition, if you're interested in being credited, please add yourself to the locale file as translator. See the example below (both the `<email/>` and `</uri>` elements are optional):
+
+```xml
+<info>
+  <translator>
+    <name>John Doe</name>
+    <email>john.doe@citationstyles.org</email>
+    <uri>https://citationstyles.org/</uri>
+  </translator>
+  <rights license="http://creativecommons.org/licenses/by-sa/3.0/">This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 License</rights>
+  <updated>2019-01-01T12:00:00+00:00</updated>
+</info>
+```