- Change distinct -> typedef.

- Order of attribute declaration is changed for `alias`.
- Added `LANGUAGE_DEV_VERSION` env constant.
- Rename `anyfault` -> `fault`.
- Changed `fault` -> `faultdef`.
- Added `attrdef` instead of `alias` for attribute aliases.

test/test_suite/errors/error_regression_2.c3t

@@ -45,7 +45,7 @@ macro dupe(value)
 	return temp;
 }
 
-fault BAD_READ, OUT_OF_MEMORY;
+faultdef BAD_READ, OUT_OF_MEMORY;
 
 fn Doc? readDoc(char[] url)
 {
@@ -85,7 +85,7 @@ fn Summary readAndBuildSummary(char[] url)
 }
 
 
-fault  TITLE_MISSING;
+faultdef  TITLE_MISSING;
 
 fn bool? isTitleNonEmpty(Doc doc)
 {
@@ -105,7 +105,7 @@ fn char* bool_to_string(bool b)
 {
 	return b ? "true" : "false";
 }
-fn char* nameFromError(anyfault e)
+fn char* nameFromError(fault e)
 {
 	switch (e)
 	{