Bugfix: Reserved parameter IKI expansion is not adding spaces and the "top" reserved...

Bugfix: Reserved parameter IKI expansion is not adding spaces and the "top" reserved parameter should always end in a slash.

The IKI expansion on reserved parameters, such as "parameter:"fakefile"", should include spaces as appropriate.
For example, given a call to "fake -f my_fakefile", the parameter:"fakefile" should expand into "-f my_fakefile" but is instead expanding into "-fmy_fakefile".

For security reasons, the expanded paths, such as parameter:"top", should always have a trailing slash.
Consider "rm -Rf parameter:"top"tmp" vs "rm -Rf parameter:"top"/tmp".
On the left side, if parameter:"top" resolves into an empty string, then the command is: "rm -Rf tmp".
On the right side, if parameter:"top" resolves into an empty string, then the command is: "rm -Rf /tmp".
The right side would end up destroying a path outside of the project root, such as "/tmp"!