Update to 8.0.50

Changelog:
Tomcat 8.0.50 (violetagg)

Catalina
    Fix: Prevent a stack trace being written to standard out when running on Java 10 due to changes in the LogManager implementation. (markt)
    Fix: Avoid duplicate load attempts if one has been made already. (remm)
    Fix: Avoid NPE in ThreadLocalLeakPreventionListener if there is no Engine. (remm)
    Fix: 62000: When a JNDI reference cannot be resolved, ensure that the root cause exception is reported rather than swallowed. (markt)
    Fix: 62036: When caching an authenticated user Principal in the session when the web application is configured with the NonLoginAuthenticator, cache the internal Principal object rather than the user facing Principal object as Tomcat requires the internal object to correctly process later authorization checks. (markt)
    Fix: 62067: Correctly apply security constraints mapped to the context root using a URL pattern of "". (markt)
    Fix: When using Tomcat embedded, only perform Authenticator configuration once during web application start. (markt)
    Fix: Process all ServletSecurity annotations at web application start rather than at servlet load time to ensure constraints are applied consistently. (markt)
    Fix: Minor optimization when calling class tranformers. (rjung)

Web applications
    Add: 48672: Add documentation for the Host Manager web application. Patch provided by Marek Czernek. (markt)

Other
    Update: Update the NSIS Installer used to build the Windows installer to version 3.03. (kkolinko)

(ryoon)