Upgrade to logback 1.1.6

LogbackValve (in logback-access) now attempts to load the configuration file as a resource if it cannot be found on the filesystem (LOGBACK-1069). This is helpful in scenarios where applications are using an embedded Tomcat server.

JMXConfigurator.reloadDefaultConfiguration() method now tolerates programmatic configuration without a URL. This change was provided by Vedran Pavic in PR 302.

RollingFileAppender will output an error message if the date time pattern in the %d token within the fileNamePattern is not collision free. This fixes LOGBACK-1137. In a similar vein, every instance of FileAppender will now detect if it shares the same File option value as given for an appender defined earlier. In addition, RollingFileAppender instances now check for colliding FileNamePattern values.

Fixed NullPointerException thrown by RollingFileAppender if the name of the rollover target path did not contain a parent. This issue was reported in LOGBACK-1054 by Paulius Matulionis. Analysis of the problem and the relevant PR was provided by Ferenc Palkovics.

BasicConfigurator.configure method call executes significatly faster. Improved documentation for configuration using JDK 1.6 service-provider facility. These changes are in response to LOGBACK-1141 requesting faster logback start-up time.

Fixed issue with variable substitution with the value ending in a colon. This problem was reported in LOGBACK-1140 by Eric Cook.