Revert "Completely remove uses of example-based"

This reverts commit 69cea20dac.

.ghci

@@ -1,2 +1,2 @@
-:set -isrc/compiler -isrc/binary -isrc/runtime/haskell -isrc/server -isrc/server/transfer -idist/build/autogen -idist/build
+:set -isrc/compiler -isrc/binary -isrc/runtime/haskell -isrc/server -isrc/example-based -isrc/server/transfer -idist/build/autogen -idist/build
 :set -fwarn-unused-imports -optP-DSERVER_MODE -optP-DUSE_INTERRUPT -optP-DCC_LAZY -optP-include -optPdist/build/autogen/cabal_macros.h -odir dist/build/gf/gf-tmp -hidir dist/build/gf/gf-tmp -stubdir dist/build/gf/gf-tmp

gf.cabal

@@ -287,7 +287,9 @@ Library
       CGIUtils
       Cache
       Fold
-    hs-source-dirs: src/server src/server/transfer
+      ExampleDemo
+      ExampleService
+    hs-source-dirs: src/server src/server/transfer src/example-based
 
   if flag(interrupt)
     cpp-options: -DUSE_INTERRUPT

src/compiler/GF/Server.hs

@@ -43,6 +43,7 @@ import GF.Infra.UseIO(readBinaryFile,writeBinaryFile,ePutStrLn)
 import GF.Infra.SIO(captureSIO)
 import GF.Data.Utilities(apSnd,mapSnd)
 import qualified PGFService as PS
+import qualified ExampleService as ES
 import Data.Version(showVersion)
 import Paths_gf(getDataDir,version)
 import GF.Infra.BuildInfo (buildInfo)
@@ -170,6 +171,7 @@ handle logLn documentroot state0 cache execute1 stateVar
                (_  ,_             ,".pgf") -> do --debug $ "PGF service: "++path
                                                  wrapCGI $ PS.cgiMain' cache path
                (dir,"grammars.cgi",_     ) -> grammarList dir (decoded qs)
+               (dir  ,"exb.fcgi"  ,_    ) -> wrapCGI $ ES.cgiMain' root dir (PS.pgfCache cache)
                _ -> serveStaticFile rpath path
              where path = translatePath rpath
            _ -> return $ resp400 upath