[vala/0.42] docs: Add a basic CONTRIBUTING.md file that links to the relevant Wiki page

[Rico Tzschichholz <ricotz src gnome org>]

commit e3420b7ddf838b145d8e2bb9d8d39615f8be6b2e
Author: Alistair Thomas <astavale yahoo co uk>
Date:   Sat Jan 5 20:41:00 2019 +0000

    docs: Add a basic CONTRIBUTING.md file that links to the relevant Wiki page

 CONTRIBUTING.md | 1 +
 1 file changed, 1 insertion(+)
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diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 000000000..b69f8b00b
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1 @@
+Please read our wiki page [Documentation for Contributors to 
Vala](https://wiki.gnome.org/Projects/Vala/DeveloperDocumentation)