Improve documentation (particularly on configuration) and the issue template

scripts/print_language_list.py

@@ -0,0 +1,14 @@
+"""
+Prints the list of supported languages, for use in the project.yml template
+"""
+
+from solidlsp.ls_config import Language
+
+if __name__ == "__main__":
+    lang_strings = sorted([l.value for l in Language])
+    max_len = max(len(s) for s in lang_strings)
+    fmt = f"%-{max_len+2}s"
+    for i, l in enumerate(lang_strings):
+        if i % 5 == 0:
+            print("\n# ", end="")
+        print("  " + fmt % l, end="")