Add installer

* start

* Add tests

* Clean up changes

* Update tool-cache we consume

* Use custom 7zr

node_modules/@actions/core/lib/command.d.ts

@@ -0,0 +1,16 @@
+interface CommandProperties {
+    [key: string]: string;
+}
+/**
+ * Commands
+ *
+ * Command Format:
+ *   ##[name key=value;key=value]message
+ *
+ * Examples:
+ *   ##[warning]This is the user warning message
+ *   ##[set-secret name=mypassword]definatelyNotAPassword!
+ */
+export declare function issueCommand(command: string, properties: CommandProperties, message: string): void;
+export declare function issue(name: string, message: string): void;
+export {};