Bug 1082554 (part 1) - Remove tools/performance/pageload/, which is ancient and unused. r=jmaher.

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extra : rebase_source : a1e034264f6c9d5a6ad2ff48f5426a8ec27aa133
Bug 1082554 (part 2) - Remove tools/performance/startup/, which is ancient and unused. r=jmaher.

--HG--
extra : rebase_source : e5236f362fc4829a3586789a85d02b994a80b4e5
Bug 1082554 (part 3) - Move diff-talos.py from tools/performance/ to testing/talos/. r=jmaher.
DONTBUILD because NPOTB.

--HG--
rename : tools/performance/diff-talos.py => testing/talos/diff-talos.py