Gemini fusion annotation

GEMINI set_somatic:
* Removed all the default filters for somatic (depth: 30, min_alt_frac, etc) because they were too stringent to be useful and make assumptions about the depth.
* Now the default behavior for a somatic variant is simply: REF in normal, non-REF in tumor, with stringent filtering still available through command line parameters.

Gemini fusions:
* Proper strand-awareness
* Properly annotates single line (including intrachromosomal) variants