Improvements in documentation

Documentation updates to be considered:

• The custom api_doc Sphinx extension uses hardcoded paths
• Sensor_OSI: FailureProbability undocumented
• Add boost package dependency
• Describe INSTALL_EXTRA_RUNTIME_DEPS
• Clarify usage of 180° heading when specifying an Agent in a Scenario with positive lane ids
• Improve openPASS overview
• Scenario simulation tutorial uses outdated paths
• Master/Slave terms still present in images