CNV CorrectGCBias: Shl doc correct gc bias

[sooheelee]

• Besides the usual doc changes, updated the following:

  
      oneLineSummary = "Correct for per-sample GC bias effects",
      summary = "Correct coverage in read counts by estimating per-sample bias as a function of target GC " +
              "content and dividing input coverage by these derived bias curves.",

to refer to per-target instead of per-sample.

• In addition, updated the output name of AnnotateTargets.java to match the input of CorrectGCBias: targets.annotated.tsv

[samuelklee]

Also, don't forget to squash before merging!