File: ChangeLog — Documentation for command

Switch to use require_relative to improve load-times.
Allow passing sudo specific keyword arguments in CommandMapper::Command#sudo_command to CommandMapper::Command.run.
Allow CommandMapper::Sudo's preserve_env attribute to accept an optional value.

Properly validate in CommandMapper::OptionValue#validate when an option, who's value is not required, is given true.
Omit nil arguments from CommandMapper::Command#command_argv if the argument is not required.
Improve validation error message for CommandMapper::Types::Num when initialized with a range: value.
Improve validation error message for CommandMapper::Types::Map and CommandMapper::Types::Enum.

Added CommandMapper::Command.spawn and CommandMapper::Command#spawn_command.
Added checks to CommandMapper::Command.option, CommandMapper::Command.argument, and CommandMapper::Command.subcommand to avoid overwriting an existing option/argument/subcommand with the same name.
Added the value_in_flag: keyword argument to CommandMapper::Command.option which indicates an option's value should be appended to the flag (ex: -Fvalue).
Added the range: keyword argument to CommandMapper::Types::Num#initialize for specifying the acceptable range of numbers.
Allow options with equals: true (aka --opt=...) or value_in_flag: true (aka -Fvalue) to accept values that start with a - character.

Fixed a bug where CommandMapper::Command.command_name was not checking the superclass for the command_name, if no command "..." was defined in the subclass.