Resolve "Use recalbox.conf variable for ParseGamelistOnly and hidesystemview"

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Closes #9 (closed)

Changes :

• ParseGamelistOnly and hidesystemview were in ES Settings (es_settings.xml) configuration, they are now managed only with RecalboxConfig (directly from recalbox.conf)
• Changed ALL system.es.**** to emulationstation.* variables in recalbox.conf and ES

Related to: https://github.com/recalbox/recalbox-buildroot/pull/658