Adding minor usage docs

git-svn-id: file:///humgen/gsa-scr1/gsa-engineering/svn_contents/trunk@4765 348d0f76-0448-11de-a6fe-93d51630548a

java/src/org/broadinstitute/sting/gatk/walkers/genotyper/UGCalcLikelihoods.java

@@ -41,6 +41,7 @@ import java.util.*;
 /**
  * Uses the UG engine to determine per-sample genotype likelihoods and emits them as a VCF (using PLs).
  * Absolutely not supported or recommended for public use.
+ * Run this as you would the UnifiedGenotyper.
  */
 @Reference(window=@Window(start=-200,stop=200))
 @By(DataSource.READS)

java/src/org/broadinstitute/sting/gatk/walkers/genotyper/UGCallVariants.java

@@ -43,6 +43,8 @@ import java.util.*;
 /**
  * Uses the UG engine to call variants based off of VCFs annotated with GLs (or PLs).
  * Absolutely not supported or recommended for public use.
+ * Run this as you would the UnifiedGenotyper, except that instead of '-I reads' it expects any number
+ * of GL/PL-annotated VCFs bound to a name starting with 'variant'.
  */
 public class UGCallVariants extends RodWalker<VariantCallContext, Integer> {