Include SLF libs, Logback libs, and Logback config
Replace LogHelper with SLF4J Logger anywhere it is possible without an
error.
Provide Markers class
Replace calls to verbose() with trace()
Change calls to log.user() to log.info().
Use the USER_MARKER for any log.user() calls.
Now you'll be able to log.error(USER_MARKER, "whatever...")
Remove unused Application imports
Replace all client calls with SLF calls
Addition for aerodynamic properties of falling stages
Write-up on lower stage descent
Technical documentation update on lower stages
Lower stage optimization files
Merge remote-tracking branch 'bkuker/slf-client' into startup

Conflicts:
	core/.classpath
	core/src/net/sf/openrocket/database/Database.java
	core/src/net/sf/openrocket/database/ThrustCurveMotorSetDatabase.java
	core/src/net/sf/openrocket/document/OpenRocketDocument.java
	core/src/net/sf/openrocket/document/Simulation.java
	core/src/net/sf/openrocket/file/openrocket/OpenRocketSaver.java
	core/src/net/sf/openrocket/file/openrocket/importt/OpenRocketLoader.java
	core/src/net/sf/openrocket/file/rocksim/export/RocksimSaver.java
	core/src/net/sf/openrocket/gui/customexpression/CustomExpressionDialog.java
	core/src/net/sf/openrocket/gui/customexpression/ExpressionBuilderDialog.java
	core/src/net/sf/openrocket/gui/customexpression/OperatorSelector.java
	core/src/net/sf/openrocket/gui/customexpression/VariableSelector.java
	core/src/net/sf/openrocket/gui/dialogs/MotorDatabaseLoadingDialog.java
	core/src/net/sf/openrocket/gui/dialogs/preferences/PreferencesDialog.java
	core/src/net/sf/openrocket/gui/figure3d/ComponentRenderer.java
	core/src/net/sf/openrocket/gui/figure3d/RocketFigure3d.java
	core/src/net/sf/openrocket/gui/main/BasicFrame.java
	core/src/net/sf/openrocket/gui/print/visitor/CenteringRingStrategy.java
	core/src/net/sf/openrocket/gui/print/visitor/FinSetPrintStrategy.java
	core/src/net/sf/openrocket/gui/print/visitor/PageFitPrintStrategy.java
	core/src/net/sf/openrocket/gui/print/visitor/TransitionStrategy.java
	core/src/net/sf/openrocket/gui/util/OpenFileWorker.java
	core/src/net/sf/openrocket/motor/ThrustCurveMotor.java
	core/src/net/sf/openrocket/rocketcomponent/Rocket.java
	core/src/net/sf/openrocket/rocketcomponent/RocketComponent.java
	core/src/net/sf/openrocket/simulation/BasicEventSimulationEngine.java
	core/src/net/sf/openrocket/simulation/SimulationOptions.java
	core/src/net/sf/openrocket/simulation/customexpression/CustomExpression.java
	core/src/net/sf/openrocket/simulation/customexpression/CustomExpressionSimulationListener.java
	core/src/net/sf/openrocket/startup/ConcurrentLoadingThrustCurveMotorSetDatabase.java
	core/src/net/sf/openrocket/util/AbstractChangeSource.java
	core/src/net/sf/openrocket/util/Coordinate.java
Use slf4j for all logging within the application.
Merge branch 'doc-lower-stage'
Update technical documentation
Quiet JarInJarStarter unless openrocket.debug is set.
Removed horrible static initialization of logging system and instead
rely on magic - the fact we are using logback classic and the logger is
named "buffer".
Added STDERR log level and appropriate infrastructure to capture
System.err.println().  This is reported in the debug dialog and in bug
reports.
Button up some details.  Only issue messages to console when
-Dopenrocket.debug is defined.  Fixed the jar to include the slf4j and
logback jars.  Fixed source attachement for logback-core jar.
Do all logback configuration in java so we can have stand alone
applications use a different configuration.  Removed unneeded methods.