Bug in trunk/ocl Reporters fixed

A presumably innocent 'cleanup' commit a month ago caused the reporters to no
longer plot headers and take incorrect timestamps. The effects of this bug
were noted by Ruben 3 days later, but did not address all issues. I've
committed (and tested) the final fix in r29019. FYI, This bug did not
influence the OCL 1.4 branch.

Peter

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r29019 | psoetens | 2008-03-04 22:04:03 +0100 (di, 04 mrt 2008) | 1 line

Fix bug where startHook() of ReportingComponent was not called, causing faulty
timestamps and no header printing.
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r28926 | rsmits | 2008-02-08 09:24:38 +0100 (vr, 08 feb 2008) | 1 line

changing startup&shutdown to startHook&stopHook, to stop the complaining about
no marshallers inserted
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r28906 | psoetens | 2008-02-05 10:15:34 +0100 (di, 05 feb 2008) | 1 line

Make ReportingComponent a bit more OCL1.4 compliant by using the *Hook()
functions.
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r28889 | tdelaet | 2008-01-30 15:39:51 +0100 (wo, 30 jan 2008) | 4 lines

Change to reporter to get the following behavior:
only add data to the report file when snapshot is called for the case when a
nonPeriodic activity is attached to the reporter