scripts/fscan.py gap_error (gap_energy_error) removed as it was based on buggy spec macros
scripts/gap_scan.py prepared for u27c calib handling

backlash handling removed
undulator status checked before changing velocity or moving
default harmonic order taken from self.parameters.gscan_order rather than being 1

scripts/fscan_pm600.prog.py added class ID26FscanCyclicTrajectory hacking CyclicTrajectory to remove last pvt point in case of more than 1 cycle

scripts/fscan* cleanup context manager completed, check controller state is idle before programming trajectory

scripts/fscan.py and fscan_pm600_prog.py refactoring continued / PM600 program loaded only if necessary

                                        and PersistantInstances into ID26GlobalInstance

using PersistantInstances for parameters handling
some prints and comments added

scripts/beamline_parameters.py added PersistantInstances class to address ID26Parameters object as dictionaries

deleted unused ConfigParameterInstances class
fix bug in ID26Parameters _reset_parameters() method no longer decorated

scripts/fscan.py fscanwhite() to use opiom multiplexer and pm600 musst triggering, and zaptime() to not address the pm600 at all.