Add tests and update licenses (#458)

Replace LGPL from past commit with Apache License 2.0 for the newly created projects:
- in Platforms/*
- TactilityKernel

Add license headers to source code in:
- in Platforms/*
- TactilityKernel
- TactilityFreeRtos

Updated LICENSE.md

Documentation/ideas.md

@@ -2,7 +2,7 @@
 
 ## Before release
 
-- Add `// SPDX-License-Identifier: LGPL-3.0-only` and similar license mentions to individual files in the project
+- Add `// SPDX-License-Identifier: GPL-3.0-only` and `// SPDX-License-Identifier: Apache-2.0` to individual files in the project
 - Change ButtonControl to work with interrupts and xQueue
 - TCA9534 keyboards should use interrupts
 - GT911 drivers should use interrupts if it's stable