logging
imported changes r2078, r2079
Merge branch 'working' into proverFeatures
Brought prover weighting into alignment with learner weighting
Refactored backtrace; added it to TracingDfs
Existential requirement for some file arguments
Integrated prover weighting scheme into main methods
Merge branch 'backtrace' into svn-r2079
resolved conflicts in merge with failFast
imported changes from svn r2125
initial merge of complexFeature
added back options code for ComplexFeatureConfiguraiton file
added-back options code for Complex Feature configuration file
Merge branch 'up_working' into dev

Conflicts:
	src/edu/cmu/ml/praprolog/util/Configuration.java
ignore testcases/tmp