Documentation: fixed type and method names
Documentation: fixed syntax errors
Documentation: fixed spelling errors in descriptions
Documentation: fixed method documentation blocks with missing param names. Also improved indentation.
Documentation: using correct Lua typename 'boolean' instead of 'bool'
Documentation: using correct Lua typename 'number' instead of 'num', 'int', 'integer', 'float', 'double', or 'enum'
Documentation: using correct Lua typename 'string'
Documentation: clarified that Doxygen needs GraphViz to create class diagrams