v1.2.42

A few relatively minor changes.

• Added a "build.plotter.advanced" function that gives much greater control over highlighting and coloring. It allows the highlighting and coloring of arbitrarily defined groups and sub-groups of replicates. Should provide a solution to issue 37.
• Fixed problem with the (still under beta-testing) reference-mismatch engine in which it would store a larger buffer of the genome fasta file than actually needed. This caused extreme memory-use issues when the genome fasta file and the bam file don't have the same chromosome ordering.