Speriment

Patched npm package so it will install Speriment CSS.
Patched Python package to fix SampleFrom bug.

- `SampleFrom` is more powerful now: you can make sure you sample the same thing in certain places or make sure you don't sample the same thing in certain places.
- `banks` can take dictionaries and `SampleFrom` can specify which key (`field`) of that dictionary to sample.
- `Options` can have `resources`
- `feedback` can be a `Page`
- `Page` and `Option` `text` can be made of a list of strings and/or `SampleFrom` objects.
- Backwards incompatible: `tags` are dictionaries instead of lists now, making the `tags` argument to `speriment-output` unnecessary
- `criterion` available on all `Blocks`, not just those that contain `Pages`

Edit: patched the npm package so it will install the css file.

- Updated documentation
- Added option to require keyboard interaction instead of mouse

- Added treatments, allowing different participants to see different blocks in a balanced way.
- Fixed bugs affecting Latin square and counterbalancing.
- Fixed bug affecting conditional running of blocks.
- Fixed overzealous validation of pseudorandomization.

- Fixed behavior of `new` method
- Added counterbalancing
- Added sampling without replacement
- Fixed installation issue (pip)

The Python package is v0.2.1 because in v0.2.0 I forgot a dependency and immediately patched.

Still in beta, so test it out and let me know about any issues you run into!

The packages are now published on pip and npm. The software is only tested on Mac OSX and should be considered a beta version although that's not in the official version tag. Try it out! Just make sure to look carefully for problems while you're still in sandbox mode. Let me know about any issues you run into.