Change compat checker icon to "warning"
Renamed package class to WebEssentialsPackage

This is important in case an error occurs. No one knows what
"EditorExtensionPackage" is.
Renamed to WebEssentialsPackage
Merge pull request #1225 from am11/master

NodeExecutorBase: Detect change before writing
Merge pull request #1227 from am11/master

Release: Version 2.2.1 (nightly)
Code: Null checkes. (#1216 and #1221)