[phobos] rdmd is not compiling

[Lars Tandle Kyllingstad]

There are a lot of things wrong with rdmd.d in the "tools" repository
right now.  If I run "dmd rdmd.d", I get the following error:

    rdmd.d(313): Error: incompatible types for ((& shellQuote) ?
    (__funcliteral4)): 'string function(string arg)' and 'string
    function(string s) pure nothrow @safe'

That's easy to fix; just mark shellQuote() as @safe pure nothrow.  But
now, the compiler is saying

    rdmd.d(321): Error: undefined identifier myModules

I think a few of the recent commits need to be reverted.

-Lars