doc: reorganize sphinx toctree

This mainly affects the html output (although users generating epub or
pdf would also notice a change). The goal is twofold: make the TOC a
bit friendler and easier to navigate by introducing some hierarchy,
and allow links for nmbug and notmuch-setup.

doc/command-line.rst

@@ -0,0 +1,36 @@
+Notmuch Command Line Interface
+==============================
+
+Main commands
+-------------
+
+.. toctree::
+   :titlesonly:
+
+   man1/notmuch
+   man1/notmuch-address
+   man1/notmuch-compact
+   man1/notmuch-config
+   man1/notmuch-count
+   man1/notmuch-dump
+   man1/notmuch-emacs-mua
+   man1/notmuch-git
+   man1/notmuch-insert
+   man1/notmuch-new
+   man1/notmuch-reindex
+   man1/notmuch-reply
+   man1/notmuch-restore
+   man1/notmuch-search
+   man1/notmuch-show
+   man1/notmuch-tag
+   man5/notmuch-hooks
+
+Aliases
+-------
+  
+.. toctree::
+   :titlesonly:
+
+   nmbug <man1/notmuch-git>
+   notmuch-setup <man1/notmuch>
+   

doc/index.rst

@@ -2,34 +2,17 @@
 Welcome to notmuch's documentation!
 ===================================
 
-Contents:
+Content
+-------
 
 .. toctree::
    :titlesonly:
 
-   man1/notmuch
+   command-line
-   man1/notmuch-address
+   queries
-   man1/notmuch-compact
-   man1/notmuch-config
-   man1/notmuch-count
-   man1/notmuch-dump
    notmuch-emacs
-   man1/notmuch-emacs-mua
-   man1/notmuch-git
-   man5/notmuch-hooks
-   man1/notmuch-insert
-   man1/notmuch-new
-   man7/notmuch-properties
-   man1/notmuch-reindex
-   man1/notmuch-reply
-   man1/notmuch-restore
-   man1/notmuch-search
-   man7/notmuch-search-terms
-   man7/notmuch-sexp-queries
-   man1/notmuch-show
-   man1/notmuch-tag
    python-bindings
-
+   
 Indices and tables
 ==================
 

doc/queries.rst

@@ -0,0 +1,9 @@
+Notmuch Queries
+===============
+
+.. toctree::
+   :titlesonly:
+
+   man7/notmuch-search-terms
+   man7/notmuch-sexp-queries
+   man7/notmuch-properties