NEW IN WAF 1.9
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* Removed the split functions from Utils
* Removed the command called "update"
* Added the tool 'nobuild.py'
* Removed qt4 and kde4 from the default modules
* Made Clang detected first on many platforms, in particular on FreeBSD #1528
* Modified Utils.run_once so that it accepts a list of *args
* Removed Node.cache_sig and Node.sig #1580
* Removed __hash__ and __eq__ from Node and Task #1629
* Changed cflags in the beginning / cppflags at the end #1505
* Reduced the key size in bld.task_sigs by adding bld.node_sigs and bld.imp_sigs
* Made lazy visual studio detection the default
* Flags given in the form ${FOO}${BAR} will be merged in commands executed without a shell