1021 - Unexpected Function header.
Description
    
An attempt to invoke a Function with a header was made, where the Function does not accept a header.
    
Example
    
Config:
    Settings( 'bad' )
{
}
Output:
c:\Test\fbuild.bff(1):(9) FASTBuild Error #1021 - Settings() - Unexpected Function header.
Settings( 'bad' )
        ^
        \--here
Fix:
Settings
{
}
    