Improve REST API docs

- Better explanation for filters and filter_vars
- Update examples to use filters in the body only, don't fuck around with the URL parameters.
- Better explain actions and their intent
- More insights into config packages and their intention
- Improve API clients and add the tables from icinga2-api-examples
- Formatting for CLI requests

doc/11-cli-commands.md

@@ -22,7 +22,7 @@ Supported commands:
   * api setup (setup for API)
   * ca list (lists all certificate signing requests)
   * ca sign (signs an outstanding certificate request)
-  * console (Icinga console)
+  * console (Icinga debug console)
   * daemon (starts Icinga 2)
   * feature disable (disables specified feature)
   * feature enable (enables specified feature)
@@ -272,7 +272,7 @@ are required for executing config expressions and auto-completion.
 
 > **Note**
 >
-> The debug console does not currently support SSL certificate verification.
+> The debug console does not currently support TLS certificate verification.
 >
 > Runtime modifications are not validated and might cause the Icinga 2
 > daemon to crash or behave in an unexpected way. Use these runtime changes

doc/19-technical-concepts.md

@@ -1680,7 +1680,7 @@ Message updates are dropped when
 * The origin sender is not in a parent zone of the receiver.
 * The certificate fingerprint is in an invalid format.
 
-#### log::SetLogPosition <a id="technical-concepts-json-rpc-messages-pki-updatecertificate"></a>
+#### log::SetLogPosition <a id="technical-concepts-json-rpc-messages-log-setlogposition"></a>
 
 > Location: `apilistener.cpp` and `jsonrpcconnection.cpp`