Fixes for script auto-documentation.

- Fixing the parts of the `make restdoc` and `make doc` process that were
  broken by the last Bro script re-organization

- Generated documentation for Bro scripts derived from BiFs now use the
  original BiF source file as the "original source file" link

- Renaming of the internal POLICYDEST definition and other misc places that
  refer to "policy" scripts; that terminology doesn't make total sense now

- Added a documentation blacklist reminder test that will fail if there's
  scripts that are blacklisted from being documentated because they're still
  in progress

- Some minor Bro script changes to fix small @load dependency errors

Addresses #543

doc/scripts/source/index.rst

@@ -14,7 +14,7 @@ Contents:
    internal
    bifs
    packages
-   policy/index
+   scripts/index
 
 Indices and tables
 ==================

doc/scripts/source/internal.rst

@@ -1,5 +1,5 @@
 .. This is a stub doc to which the build process can append.
 
-Internal Policy Scripts
-=======================
+Internal Scripts
+================
 

doc/scripts/source/packages.rst

@@ -1,11 +1,15 @@
 .. This is a stub doc to which the build process can append.
 
-Policy Script Packages
-======================
+Bro Script Packages
+===================
 
-Bro has the following policy script packages (e.g. collections of related
-policy scripts).  If the package contains a ``__load__.bro`` script, it
-supports being loaded in mass as a whole directory for convenience.
+Bro has the following script packages (e.g. collections of related scripts in
+a common directory).  If the package directory contains a ``__load__.bro``
+script, it supports being loaded in mass as a whole directory for convenience.
+
+Packages/scripts in the ``base/`` directory are all loaded by default, while
+ones in ``policy/`` provide functionality and customization options that are
+more appropriate for users to decide whether they'd like to load it or not.
 
 .. toctree::
    :maxdepth: 1

doc/scripts/source/policy/index.rst

@@ -1,6 +0,0 @@
-Index of All Policy Script Documentation
-========================================
-
-.. toctree::
-   :maxdepth: 1
-

doc/scripts/source/scripts/index.rst

@@ -0,0 +1,6 @@
+Index of All Bro Script Documentation
+=====================================
+
+.. toctree::
+   :maxdepth: 1
+