Review and edit Lua docstrings

[oznogon]

• Fix several examples that use a different function name than the one being documented (setSystemCoolant using setSystemPowerFactor, setPlanetAtmosphereTexture using setPlanetSurfaceTexture, several getters and setters mixed up)
• Align examples of function usage to the arguments they actually use
• Fix some incorrect defaults
• Fix incorrect ship system heat, power, and health ranges
• Remove extraneous arguments from getters (getHeading(0))
• Remove extraneous colons from example function calls
• Add missing docstring for VisualAsteroid
• Add missing example to ModelData:setNormalMap
• Flag setBeamFireSound/setBeamFireSoundPower as not implemented
• Fix chaining order in ScanProbe example
• Fix incorrect return type on getWaypointID
• Fix incorrect scan state values in examples (full not fullscan)
• Fix claim of case-insensitivity in ScienceDatabase set/getKeyValue, removeKey
• Use "entity" or "ship" in place of legacy class names like SpaceObject or SpaceShip
• Remove legacy class names in descriptions where they no longer apply
• Remove duplicated onPickUp description and neutralize references to Artifacts and SupplyDrops
• Remove manual angle behavior described in commandFireTube (needs verification)
• Replace references to "meters" with "game units"
• Fix several typos ("netural", "electical", "consideres", etc.)
• Fix several references to incorrect source implementations (point to components/systems instead of spaceshipParts)

[daid]

at least you copied my mistake :P