Update and reorganize documentation

- Convert "Common Tasks" to "How-to Guides"
  (QubesOS/qubes-issues#6694)
- Make title capitalization consistent across docs
- Fix leftover h1 headings
- Reorganize various pages and topics
- Update permalinks to better match titles
- Create redirects for changed permalinks
- Miscellaneous cleanup

QubesOS/qubes-issues#6701

developer/services/disposablevm-implementation.md

@@ -8,7 +8,7 @@ redirect_from:
 - /doc/DVMimpl/
 - /wiki/DVMimpl/
 ref: 34
-title: DisposableVM implementation
+title: DisposableVM Implementation
 ---
 
 **Note: The content below applies to Qubes R3.2.**

developer/services/qfilecopy.md

@@ -7,10 +7,9 @@ redirect_from:
 - /doc/Qfilecopy/
 - /wiki/Qfilecopy/
 ref: 35
-title: Qfilecopy
+title: Inter-VM File Copying (qfilecopy)
 ---
 
-
 There are two cases when we need a mechanism to copy files between VMs:
 
 - "regular" file copy - when user instructs file manager to copy a given files/directories to a different VM

developer/services/qfileexchgd.md

@@ -7,7 +7,7 @@ redirect_from:
 - /doc/Qfileexchgd/
 - /wiki/Qfileexchgd/
 ref: 40
-title: Qfileexchgd
+title: qfileexchgd (deprecated)
 ---
 
 **This mechanism is obsolete as of Qubes Beta 1!**

developer/services/qmemman.md

@@ -7,10 +7,9 @@ redirect_from:
 - /doc/Qmemman/
 - /wiki/Qmemman/
 ref: 41
-title: Qmemman
+title: Qubes Memory Manager (qmemman)
 ---
 
-
 Rationale
 ---------
 

developer/services/qrexec-internals.md

@@ -8,7 +8,7 @@ redirect_from:
 - /doc/Qrexec3Implementation/
 - /wiki/Qrexec3Implementation/
 ref: 39
-title: 'Qrexec: Qubes RPC internals'
+title: 'Qrexec: Qubes RPC Internals'
 ---
 
 

developer/services/qrexec-socket-services.md

@@ -3,7 +3,7 @@ lang: en
 layout: doc
 permalink: /doc/qrexec-socket-services/
 ref: 42
-title: 'Qrexec: Socket-based services'
+title: 'Qrexec: Socket-based Services'
 ---
 
 

developer/services/qrexec.md

@@ -11,7 +11,7 @@ redirect_from:
 - /doc/Qrexec/
 - /wiki/Qrexec/
 ref: 37
-title: 'Qrexec: secure communication across domains'
+title: 'Qrexec: Secure Communication Across Domains'
 ---
 
 (*This page is about qrexec v3. For qrexec v2, see [here](/doc/qrexec2/).*)

developer/services/qrexec2.md

@@ -8,11 +8,10 @@ redirect_from:
 - /doc/Qrexec2Implementation/
 - /wiki/Qrexec2Implementation/
 ref: 38
-title: Qrexec2
+title: qrexec v2 (deprecated)
 ---
 
-
-(*This page is about qrexec v2. For qrexec v3, see [here](/doc/qrexec3/).*)
+(*This page is about qrexec v2. For qrexec v3, see [here](/doc/qrexec/).*)
 
 Qubes **qrexec** is a framework for implementing inter-VM (incl. Dom0-VM)
 services. It offers a mechanism to start programs in VMs, redirect their