Add Enterprise Edition license (#16801)

Co-authored-by: Rodrigo Nascimento <rodrigoknascimento@gmail.com>

LICENSE

-The MIT License (MIT)
+Copyright (c) 2015-2020 Rocket.Chat Technologies Corp.
+
+Portions of this software are licensed as follows:
 
-Copyright (c) 2015-2019 Rocket.Chat Technologies Corp.
+* All content that resides under the "ee/" directory of this repository, if
+  that directory exists, is licensed under the license defined in "ee/LICENSE".
+* All third-party components incorporated into the Rocket.Chat Software are
+  licensed under the original license provided by the owner of the applicable
+  component.
+* Content outside of the above-mentioned directories or restrictions above is
+  available under the MIT (Expat) license as defined below.
+
+The MIT License (MIT)
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -19,4 +29,3 @@ 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.
-

ee/LICENSE

+The Rocket.Chat Enterprise Edition (EE) license (the "EE License")
+Copyright (c) 2015-2020 Rocket.Chat Technologies Corp.
+
+With regard to the Rocket.Chat Software:
+
+This software and associated documentation files (the "Software") may only be
+used in production, if you (and any entity that you represent) have agreed to,
+and are in compliance with, the Rocket.Chat Subscription Terms of Service,
+available at https://rocket.chat/terms (the "EE Terms"), or other agreement
+governing the use of the Software, as agreed by you and Rocket.Chat, and otherwise
+have a valid Rocket.Chat Enterprise Edition subscription for the correct number
+of user seats. Subject to the foregoing sentence, you are free to modify this
+Software and publish patches to the Software. You agree that Rocket.Chat and/or
+its licensors (as applicable) retain all right, title and interest in and to all
+such modifications and/or patches, and all such modifications and/or patches may
+only be used, copied, modified, displayed, distributed, or otherwise exploited
+with a valid Rocket.Chat Enterprise Edition subscription for the correct number
+of user seats. Notwithstanding the foregoing, you may copy and modify the Software
+for development and testing purposes, without requiring a Subscription. You agree
+that Rocket.Chat and/or its licensors (as applicable) retain all right, title and
+interest in and to all such modifications. You are not granted any other rights
+beyond what is expressly stated herein.  Subject to the foregoing, it is forbidden
+to copy, merge, publish, distribute, sublicense, and/or sell the Software.
+
+This EE License applies only to the part of this Software that is not distributed
+as part of Rocket.Chat Community Edition (CE). Any part of this Software distributed
+as part of Rocket.Chat CE or is served client-side as an image, font, cascading
+stylesheet (CSS), file which produces or is compiled, arranged, augmented, or combined
+into client-side JavaScript, in whole or in part, is copyrighted under the MIT Expat
+license. The full text of this EE License 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.
+
+For all third-party components incorporated into the Rocket.Chat Software,
+those components are licensed under the original license provided by the owner
+of the applicable component.