Onecodex

- Add support (default on) for telemetry data to be sent to One Codex during a crash of the CLI _only_. Can be disabled with the `--no-telemetry` flag.
- Fix bug that would crash CLI when trying to fetch an invalid sample or analysis ID (3479a4e6d8de518a4356547a37780089de71dda4)
- Fix bug related to corrupt `~/.onecodex` credentials files when switching from anonymous to authenticated use of the CLI (8b4a376e4934b5d7f37058f1cdd13d56279acea2)

Fixes and improvements include:
- Update default page size from 20 to 200 items – greatly reducing the number of requests
- Remove `pandas` `MultiIndex`ing from internal `DataFrame` generated in `onecodex.helpers` and used by `onecodex.viz` functions. Multi-indexing requires sorting and is generally hard to work with. Columns returned by `collate_classification_results` are now simply string Tax IDs.
- Allow passing `**kwargs` from `onecodex.viz.plot_*` functions to Seaborn/Matplotlib.
- Change default plot theme to `darkgrid`. Override with `style=` keyword.
- Ignore SciPy cluster warnings in `sns.clustermap`
- Fix bug with CLI uploading for paired end gzipped data (previous regression).
- Fix issue with CLI failing to run properly if `matplotlib` existed but was not installed properly (i.e., it could be imported but its import raised an exception).
- Set `threads` to 1 by default in `onecodex.lib.upload` functions if `None` is passed in.

Minor fixes and improvements:
- Bump to latest version of `potion-client` (2.5.1)
- Fix bug affecting `.where()` queries for models that have a `public` property and not a public route (no models have both)

- Adds basic convenience plotting functions, including `plot_distance`, `plot_heatmap`, `plot_metadata`, and `plot_pca`. These are available on One Codex `Api` instances, e.g., `ocx.viz.plot_heatmap(*args, **kwargs)`.
- Adds `onecodex.helper` that includes _unstable_ helper functions for coercing samples and analyses into classifications, collating multiple classification results, etc.
- Add `onecodex.distance` module with support for several common alpha and beta diversity statistics. Additional statistics are available by calling out to [`skbio`](http://scikit-bio.org/) directly.

- Implement automatic version checking and warnings in the CLI (i.e., warn if using an outdated version of the CLI or library)

Changes include:
- Fix automatic replacement of `\t` character with `|` (warns the user)
- Support in `FASTXTranslator` for conversion of `X` to `N` and `U` to `T` (disabled by default in CLI)
- Optimized in-place validation of FASTA/Q files, including a 50% speedup for gzipped files
- Add a `--do-not-validate` flag to `onecodex upload`, which is faster at the expense of skipping in-place validation (NOT RECOMMENDED)

Other minor changes additional test coverage, simplification of the `Api.__init__` call, and better support for overriding the API base url using an environment variable.