Remove docs and fix links (betaflight#12222)

Author: haslinghuis

CONTRIBUTING.md

@@ -10,4 +10,4 @@ Please search for existing issues *before* creating new ones.
 
 # Developers
 
-Please refer to the development section in the [this folder](https://github.com/betaflight/betaflight/tree/master/docs/development).
+Please refer to the development section in the [this folder](https://betaflight.com/docs/development).

README.md

@@ -19,11 +19,11 @@ This fork differs from Baseflight and Cleanflight in that it focuses on flight p
 
 The following new requirements for pull requests adding new targets or modifying existing targets are put in place from now on:
 
-1. Read the [hardware specification](https://github.com/betaflight/betaflight/blob/master/docs/Manufacturer%20Design%20Guidelines.md)
+1. Read the [hardware specification](https://betaflight.com/docs/manufacturer/Manufacturer%20Design%20Guidelines)
 
 2. No new F3 based targets will be accepted;
 
-3. For any new target that is to be added, only a Unified Target config into https://github.com/betaflight/unified-targets/tree/master/configs/default needs to be submitted. See the [instructions](https://github.com/betaflight/betaflight/blob/master/docs/TargetMaintenance/CreatingAUnifiedTarget.md) for how to create a Unified Target configuration. If there is no Unified Target for the MCU type of the new target (see instructions above), then a 'legacy' format target definition into `src/main/target/` has to be submitted as well;
+3. For any new target that is to be added, only a Unified Target config into https://github.com/betaflight/unified-targets/tree/master/configs/default needs to be submitted. See the [instructions](https://betaflight.com/docs/manufacturer/Creating%20An%20Unified%20Target) for how to create a Unified Target configuration. If there is no Unified Target for the MCU type of the new target (see instructions above), then a 'legacy' format target definition into `src/main/target/` has to be submitted as well;
 
 4. For changes to existing targets, the change needs to be applied to the Unified Target config in https://github.com/betaflight/unified-targets/tree/master/configs/default. If no Unified Target configuration for the target exists, a new Unified Target configuration will have to be created and submitted. If there is no Unified Target for the MCU type of the new target (see instructions above), then an update to the 'legacy' format target definition in `src/main/target/` has to be submitted alongside the update to the Unified Target configuration.
 
@@ -50,7 +50,7 @@ Betaflight has the following features:
 
 ## Installation & Documentation
 
-See: https://github.com/betaflight/betaflight/wiki
+See: https://betaflight.com/docs/wiki
 
 ## Support and Developers Channel
 
@@ -81,7 +81,7 @@ Contributions are welcome and encouraged. You can contribute in many ways:
 * new feature ideas & suggestions;
 * provide a new translation for configurator, or help us maintain the existing ones (see [below](#Translators)).
 
-The best place to start is the Betaflight Slack (registration [here](https://slack.betaflight.com/)). Next place is the github issue tracker:
+The best place to start is the Betaflight Discord (registration [here](https://discord.gg/n4E6ak4u3c)). Next place is the github issue tracker:
 
 https://github.com/betaflight/betaflight/issues
 https://github.com/betaflight/betaflight-configurator/issues
@@ -95,7 +95,7 @@ If you want to contribute financially on an ongoing basis, you should consider b
 ## Developers
 
 Contribution of bugfixes and new features is encouraged. Please be aware that we have a thorough review process for pull requests, and be prepared to explain what you want to achieve with your pull request.
-Before starting to write code, please read our [development guidelines](docs/development/Development.md ) and [coding style definition](docs/development/CodingStyle.md).
+Before starting to write code, please read our [development guidelines](https://betaflight.com/docs/development/development) and [coding style definition](https://betaflight.com/docs/development/development/CodingStyle).
 
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