Update all licenses (#3002)

# Description of Changes

We recently merged several repos together. This PR clarifies the license
terms for several subdirectories, as well as the relationship between
the licenses.

The licenses in our subdirectories have become symbolic links to
licenses in our toplevel `licenses` directory. For any particular
subdirectory's license file in the diff, you can click `... -> View
file` and then click on the text that says "Symbolic Link" on that page.
This will take you to the license file that it links to.

I have also updated the `tools/upgrade-version` script to update the
change date in the new `licenses/BSL.txt` file.

# API and ABI breaking changes

None.

# Expected complexity level and risk

1

# Testing

None. Only changes to license files.

---------

Co-authored-by: Zeke Foppa <[email protected]>

Author: bfops

LICENSE.txt

@@ -40,6 +40,34 @@ License text copyright (c) 2017 MariaDB Corporation Ab, All Rights Reserved.
 
 -----------------------------------------------------------------------------
 
+Base License and Subdirectory Specific Licenses
+
+1. Repository-Wide License
+Except as provided in Section 2 below, the contents of this repository are licensed under the Business Source License (“BSL”), which includes a change date resulting in a licensing change to the GNU Affero General Public License v3.0 with Linking Exception on that date. See the full text of the BSL and AGPL with Linking Exception in this file below.
+
+2. Subdirectory-Specific Licenses
+Certain subdirectories within this repository are licensed under different terms.
+
+If a subdirectory contains its own LICENSE or LICENSE.txt file, the terms in that file apply exclusively to all files and subfolders within that subdirectory.
+
+In the event of any conflict between this base license and a subdirectory’s license, the base license will govern for that subdirectory’s contents.
+
+3. Contributor Acknowledgement
+By contributing to this repository, you agree that:
+
+Your contributions will be licensed under the license applicable to the directory or subdirectory in which your contribution is made.
+
+If you contribute to multiple subdirectories, the applicable license for each subdirectory will apply to your contributions in that subdirectory.
+
+4. Reading the Applicable License
+Before using, modifying, or distributing code from this repository, you must read:
+
+This base LICENSE.txt file for the overall repository license.
+
+Any LICENSE or LICENSE.txt file in a subdirectory that you intend to use or contribute to.
+
+-----------------------------------------------------------------------------
+
 Business Source License 1.1
 
 Terms

crates/auth/LICENSE

@@ -0,0 +1 @@
+../../licenses/BSL.txt

crates/auth/LICENSE

@@ -0,0 +1 @@
+../../licenses/BSL.txt

crates/bench/LICENSE

@@ -0,0 +1 @@
+../../licenses/BSL.txt

crates/bench/LICENSE

@@ -0,0 +1 @@
+../../licenses/BSL.txt