chkname.c, pwck.c, useradd.c, usermod.c, newusers.c: Allow names that do not conform to standards

Closes #121.

Changelog: squashed commits fixing tab style
Changelog: update 'return true' to match file's style (no parens).

man/useradd.8.xml

@@ -126,6 +126,16 @@
     <para>The options which apply to the <command>useradd</command> command are:
     </para>
     <variablelist remap='IP'>
+      <varlistentry>
+	<term>
+	  <option>--badname</option>&nbsp;
+	</term>
+	<listitem>
+	  <para>
+        Allow names that do not conform to standards.
+	  </para>
+	</listitem>
+      </varlistentry>
       <varlistentry>
 	<term>
 	  <option>-b</option>, <option>--base-dir</option>&nbsp;<replaceable>BASE_DIR</replaceable>