documentation: add commmand-line option reference

Currently, that's just the output of `pmdb --help`, but it may
get more detailed in the future.

Author: striezel

documentation/SUMMARY.md

@@ -6,6 +6,8 @@
 
 [Using pmdb](basic_usage.md)
 
+[Command-line options](extended_usage.md)
+
 [Location of pmdb's files](directories.md)
 
 [Templates](templates.md)

documentation/basic_usage.md

@@ -124,3 +124,8 @@ And `pmdb` will then open the generated HTML file in the browser.
 In general, `pmdb` will let you combine paramaters and tasks freely most of the
 time. (There are some exceptions like the `--help` or `--version` parameters
 which will just print the information and then exit.)
+
+## Further options
+
+`pmdb` provides more options, but those are usually not required that often. To
+see them, take a look at the [command-line option reference](extended_usage.md).

documentation/extended_usage.md

@@ -0,0 +1,73 @@
+# pmdb command-line options
+
+`pmdb` provides the following command-line options:
+
+```
+pmdb
+
+Manages private messages exported from vBulletin in XML format.
+
+options:
+  --help            - Displays this help message and quits.
+  -?                - same as --help
+  --version         - Displays the version of the program and quits.
+  -v                - same as --version
+  -xml FILENAME     - Sets the name of the XML file that contains the private
+                      messages to FILENAME. Must not be omitted.
+  --xml=FILENAME    - same as -xml
+  --load-default    - Tries to load messages from the default directory.
+                      This option is enabled by default.
+  --no-load-default - Prevents the program from automatically loading messages
+                      from the default directory.
+                      Mutually exclusive with --load-default.
+  --load=DIR        - Tries to load all messages saved in the directory DIR.
+                      This option can be given more than once, however the
+                      directory has to be different every time.
+  --save            - All messages will be saved after the XML files were read
+                      and the messages from the load directories have been
+                      loaded. Enabled by default.
+  --no-save         - Prevents the program from saving any read messages.
+                      Mutually exclusive with --save.
+  --compress        - Save and load operations (see --save and --load) will use
+                      compression, i.e. messages are compressed using zlib
+                      before they are saved to files, and they will be decom-
+                      pressed when they are loaded from files. By default,
+                      messages will NOT be compressed for backwards compatibi-
+                      lity with earlier pmdb versions.
+  --no-save-check   - This option prevents the program from checking the
+                      compression status of messages when saving to an existing
+                      directory. Note that this is not recommended, because it
+                      could result in a mixup where a directory contains both
+                      compressed and uncompressed messages, making some of the
+                      messages unreadable by the program.
+  --html            - Creates HTML files for every message.
+  --xhtml           - Like --html, but use XHTML instead of HTML.
+  --no-br           - Do not convert new line characters to line breaks in
+                      (X)HTML output.
+  --no-list         - Do not parse [LIST] codes when creating HTML files.
+  --table=CLASS     - Sets the class for grids in <table> to CLASS.
+                      Must occur together with --row and --cell.
+  --row=CLASS       - Sets the class for grids in <tr> to CLASS.
+                      Must occur together with --table and --cell.
+  --cell=CLASS      - Sets the class for grids in <td> to CLASS.
+                      Must occur together with --table and --row.
+  --std-classes     - Sets the 'standard' classes for the three class options.
+                      This is equivalent to specifying all these parameters:
+                          --table=grid_table
+                          --row=grid_tr
+                          --cell=grid_td
+  --no-open         - Usually the program tries to open the generated HTML
+                      files in a web browser for viewing. If this option is
+                      given, no such attempt is made.
+  --subset-check    - Search for messages with texts that are completely
+                      contained in other messages, too.
+  --list-from X     - List all messages that were sent by user X, where X stands
+                      for the name of the user (not the numeric user id).
+                      Can occur multiple times for more than one user.
+  --list-to X       - List all messages that were sent to user X, where X stands
+                      for the name of the user (not the numeric user id).
+                      Can occur multiple times for more than one user.
+```
+
+Most of those options can be combined freely, except those that are obviously
+contradicting each other, like `--save` and `--no-save`  for example.