Replace jqueryui license with nouislider license

We’ve switched from jqueryui sliders to nouisliders.

Author: jasongrout

jupyterlab_widgets/LICENSE

@@ -197,51 +197,29 @@ ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 ------------------------------------------------------------------------------
-From jquery-ui/LICENSE.txt
+From noUISlider/LICENSE.md (https://github.com/leongersen/noUiSlider/blob/eca62f9e56aaf02f0841b36e7993adf8db3721d5/LICENSE.md)
 
-Copyright jQuery Foundation and other contributors, https://jquery.org/
+MIT License
 
-This software consists of voluntary contributions made by many
-individuals. For exact contribution history, see the revision history
-available at https://github.com/jquery/jquery-ui
-
-The following license applies to all parts of this software except as
-documented below:
-
-====
-
-Permission is hereby granted, free of charge, to any person obtaining
-a copy of this software and associated documentation files (the
-"Software"), to deal in the Software without restriction, including
-without limitation the rights to use, copy, modify, merge, publish,
-distribute, sublicense, and/or sell copies of the Software, and to
-permit persons to whom the Software is furnished to do so, subject to
-the following conditions:
+Copyright (c) 2019 Léon Gersen
 
-The above copyright notice and this permission notice shall be
-included in all copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-
-====
-
-Copyright and related rights for sample code are waived via CC0. Sample
-code is defined as all source code contained within the demos directory.
-
-CC0: http://creativecommons.org/publicdomain/zero/1.0/
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
 
-====
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
 
-All files located in the node_modules and external directories are
-externally maintained libraries used by this software which have their
-own licenses; we recommend you read them, as their terms may differ from
-the terms above.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
 
 ------------------------------------------------------------------
 From jquery/LICENSE.txt