Re-levelization: move non-docs content, rename content→docs

For better URLs, the content folder has been renamed 'docs' and all
other files have been moved up a level. Also, non-docs images have been
moved to the static folder at the top level where they belong.

Many relative paths had to be fixed to make this work.

docs/infrastructure/testing-and-auditing/advance-the-ledger-in-stand-alone-mode.md

@@ -28,4 +28,4 @@ Whenever `rippled` closes a ledger, it reorders the transactions according to a
     - [server_info method][]
     - [`rippled` Commandline Usage](../commandline-usage.md)
 
-{% raw-partial file="/_snippets/common-links.md" /%}
+{% raw-partial file="/docs/_snippets/common-links.md" /%}

docs/infrastructure/testing-and-auditing/load-a-saved-ledger-in-stand-alone-mode.md

@@ -84,6 +84,6 @@ This puts the transactions in canonical order and processes them to make a close
     - [server_info method][]
     - [`rippled` Commandline Usage](../commandline-usage.md)
 - **Use Cases:**
-    - [Contribute Code to the XRP Ledger](../../resources/contribute-code/contribute-code.md)
+    - [Contribute Code to the XRP Ledger](/resources/contribute-code/index.md)
 
-{% raw-partial file="/_snippets/common-links.md" /%}
+{% raw-partial file="/docs/_snippets/common-links.md" /%}

docs/infrastructure/testing-and-auditing/run-private-network-with-docker.md

@@ -28,7 +28,7 @@ In this tutorial, you will learn:
 
 The following diagram shows a high-level overview of the containerized private network that you will set up.
 
-[{% inline-svg file="/img/xrp-ledger-private-network-docker.svg" /%}](/img/xrp-ledger-private-network-docker.svg "Figure 1: Diagram of a three node containerized private ledger network")
+[{% inline-svg file="/docs/img/xrp-ledger-private-network-docker.svg" /%}](/docs/img/xrp-ledger-private-network-docker.svg "Figure 1: Diagram of a three node containerized private ledger network")
 
 ## Prerequisites
 

docs/infrastructure/testing-and-auditing/start-a-new-genesis-ledger-in-stand-alone-mode.md

@@ -43,6 +43,6 @@ By default, a new genesis ledger has no [amendments](../../concepts/networks-and
     - [server_info method][]
     - [`rippled` Commandline Usage](../commandline-usage.md)
 - **Use Cases:**
-    - [Contribute Code to the XRP Ledger](../../resources/contribute-code/contribute-code.md)
+    - [Contribute Code to the XRP Ledger](/resources/contribute-code/index.md)
 
-{% raw-partial file="/_snippets/common-links.md" /%}
+{% raw-partial file="/docs/_snippets/common-links.md" /%}