Add erp5_scalability_data bt5

Contain objects and scripts needed to perform scalability tests.
benchmark: modify and add new benchmark

These benchmarks are used during scalability tests.
A file which contains list of scalability users is also added.
erp5-util-benchmark: cleanup useless spaces
erp5-util-benchmark: use list comprehension instead of listing 1000 entries
browser: change xpath expression to take into account <tbody> tag.
testnode: Modify testnode structure to include scalability tests.

Testnode code has been splitted. Runner class has been created for
each test types (unit and scalability).
Communication with SlapOS and ERP5 Master has been added.
Add scalability test suite runner.

This runner is used by scalability test, it communicates
with ERP5 Master and launch test suite (using performance_tester).
erp5-util-scalability: cleanup useless spaces
performance_tester: add command line options to use different paths.

Add option to specify several path where to find users file(s),
and benchmark suite file(s).
erp5-util-banchmark: cleanup useless spaces
process: change REPEAT_NUMBER_BEFORE_FLUSHING from 10 to 1

This commit in order to force the flush of files
containing test informations after each iteration.
erp5-util-taskdistribution: TestResultProxyProxy class seems useless

We only only need an usual test result proxy, we only need the additional
method getRunningTestCase
erp5-util: remove useless duplications of test in testERP5TestNode