https://bugs.webkit.org/show_bug.cgi?id=109246

Reviewed by Philippe Normand.

Split up configure.ac into sections based on different "phases"
of configuration. This should make it easier to find what you are
looking for as well as creating a "right" place to put things.
A nice side effect of this is that we can share the different
modules with a gyp build.

* Source/autotools/CheckSystemAndBasicDependencies.m4: Added.
* Source/autotools/FindDependencies.m4: Added.
* Source/autotools/PrintBuildConfiguration.m4: Added.
* Source/autotools/ReadCommandLineArguments.m4: Added.
* Source/autotools/SetupAutoconfHeader.m4: Added.
* Source/autotools/SetupAutomake.m4: Added.
* Source/autotools/SetupCompilerFlags.m4: Added.
* Source/autotools/SetupLibtool.m4: Added.
* Source/autotools/Versions.m4: Added.
* configure.ac:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@142284 268f45cc-cd09-0410-ab3c-d52691b4dbfc