Nwbwidgets

New Features
* Improvements on Panel Docker file, including path for read-only mount to access local files [PR 299](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/299)
* Panel error handling with message output [PR 299](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/299)
* New flag argument on Panel to enable/disable warnings [PR 299](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/299)
* Improved browsing and reading local NWB files with Panel, using ipyfilechooser [PR 300](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/300)
* Improve readibility of dandisets and files dropdown lists [PR 301](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/301)

Fixes
* Fix I/O issues when streaming data on Panel [PR 295](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/295)
* Fix plotly Figure not showing up, pinned Plotly version [PR 297](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/297)
* Fix BehavioralTimeSeries not showing up [PR 297](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/297)

Fixes
* Prevented the display of video assets on DANDI from the `Panel` dropdown. [PR 281](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/281)
* Remove `trials` from the accordion of `nwb2widget` (it will display in the `intervals` tab alongside any other `TimeIntervals`). [PR 281](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/281)
* Prevent the `ElectrodeGroupWidget` from loading if positions (specifically, `x`) are missing in conjunction with nwb-schema versions that allow those columns to be optional. [PR 280](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/280)

New Features
* Added a trialized widget for TimeSeries. [PR 232](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/232)

Dependencies
* Loosened upper bound version on `ipywidgets`. [PR 260](https://github.com/NeurodataWithoutBorders/nwbwidgets/pull/260)