Documentation of fileMode could be improved to avoid user trip hazard

The website documentation for the fileMode parameter that occurs in a number of places in the assembly descriptor format description such as [1] does show a leading 0 for its values, but it isn't clear that this is to declare the value as octal. Anyone who is used to using the chmod command on *nix doesn't expect to have to prefix the octal value with a 0, and therefore might assume the 0 to be an insignificant digit. It would be helpful to add a comment in the descriptions of these parameters that the value is interpreted as decimal unless preceded by a leading 0 to indicate an octal value.

[1] http://maven.apache.org/plugins/maven-assembly-plugin/assembly.html#class_file