Add //third_party/sqlite to dirs_to_snapshot, remove net_sql.patch

third_party/sqlite/src/autoconf/tea/README

+This is the SQLite extension for Tcl using the Tcl Extension
+Architecture (TEA).  For additional information on SQLite see
+
+        http://www.sqlite.org/
+
+
+UNIX BUILD
+==========
+
+Building under most UNIX systems is easy, just run the configure script
+and then run make. For more information about the build process, see
+the tcl/unix/README file in the Tcl src dist. The following minimal
+example will install the extension in the /opt/tcl directory.
+
+        $ cd sqlite-*-tea
+        $ ./configure --prefix=/opt/tcl
+        $ make
+        $ make install
+
+WINDOWS BUILD
+=============
+
+The recommended method to build extensions under windows is to use the
+Msys + Mingw build process. This provides a Unix-style build while
+generating native Windows binaries. Using the Msys + Mingw build tools
+means that you can use the same configure script as per the Unix build
+to create a Makefile. See the tcl/win/README file for the URL of
+the Msys + Mingw download.
+
+If you have VC++ then you may wish to use the files in the win
+subdirectory and build the extension using just VC++. These files have
+been designed to be as generic as possible but will require some
+additional maintenance by the project developer to synchronise with
+the TEA configure.in and Makefile.in files. Instructions for using the
+VC++ makefile are written in the first part of the Makefile.vc
+file.