2020-03-16 release

Changelog

@@ -1,3 +1,14 @@
+2020-03-16:
+
+- reworked error handling in std and os libraries: suppressed I/O
+  exceptions in std FILE functions and return a positive errno value
+  when it is explicit
+- output exception messages to stderr
+- added std.loadFile(), std.strerror(), std.FILE.prototype.tello()
+- added JS_GetRuntimeOpaque(), JS_SetRuntimeOpaque(), JS_NewUint32()
+- updated to Unicode 13.0.0
+- misc bug fixes
+
 2020-01-19:
 
 - keep CONFIG_BIGNUM in the makefile