Instrain

- Add "dtype='float64'" to all pd.Series() calls to supress warnings

- Change a pandas "append" statement that was making a lot of noise
- Fix a bug when scaffold names are numbere

- Include SNV pooling options (big update with lots of changes)
- Include "cov1 = pd.Series(dtype='float64')" in readComparer.py to suppress a future warning
- Remove cryptic SNVs from the nonredundant_snv_table (https://github.com/MrOlm/inStrain/issues/102)
- Only produce the run report when run in debug mode
- Various minor stylistic tweaks in runtime reporting

- Make error log more readable - https://github.com/MrOlm/inStrain/issues/79
- Correct the reporting for the amount of reads removed during filtering to account for different filtering schemes
- Adjust the docs to account fo adjusting the pairing filter (https://github.com/MrOlm/inStrain/issues/70)

- Logging handling of broken genes
- Check for sambamba in rarefaction_curve.py

- Actual traceback in the log of gene failure exception