[Tracker] Changes with Autogen/Configure, including new --enable-minimal option

[Martyn Russell <martyn lanedo com>]

Hello all,

This is just a heads up.

I've landed a large commit to configure.ac recently and also Rico 
Tzschichholz has been assisting me with some changes to the autogen.sh 
script too modernise a bit.

Autogen.sh:

  We now run gnome-autogen.sh, so building Tracker from *git* will
  require gnome-common. This shouldn't affect those building from
  tarballs.

Configure:

  I've spent some time updating configure in a few ways:

  1. Now you can use --enable-minimal, and only tracker-store is built
     and command line utilities, everything else is disabled.
  2. All ./configure arguments have been updated to use $enableval and
     $withval. This fixes some cases where the --disable-* variant is
     used. This has also fixed some cases where the AC_ARG_ENABLE or
     AC_ARG_WITH 'if-not-given' was used incorrectly.
  3. There is now a --enable-tracker-extract (default is enabled), now
     it can be disabled.
  4. There is now a --enable-tracker-writeback (default is enabled), now
     it can be disabled.
  5. Summary now reflects what is built more concisely and is much
     smaller when using --enable-minimal.
  6. After running autoscan, ./configure now has more checks for PROGS,
     HEADERS and FUNCS that are being used.
  7. AC_USE_SYSTEM_EXTENSIONS is now used adding C extensions where
     available (like _GNU_SOURCE).

For most, these changes shouldn't affect you, but you never know :)
Any problems, let me know!

--
Regards,
Martyn

Founder & Director @ Lanedo GmbH.
http://www.linkedin.com/in/martynrussell