1.0beta.18

Includes updates from the past several months of work in the dev branch, including lots of bug & perf fixes, better support for multiple alignment output (for example, limiting the number of mappings of a read per contig), an option to do index build with less memory, a daemon mode that allows SNAP to run and take commands from a pipe, and changes that make SNAP less likely to call indels when it can get the same edit distance with SNVs.