Changes to match mat package.

Renamed Vector to Slice.
Renamed CopyTo() to Copy().
Added MakeSlice() and default Make().
Added MakeSliceCopy() and MakeCopy()
Added AppendToSlice() method.
Implemented String() in terms of Fprint().
Added Cat and MutableCat.
Changed Randn() from function modifying Mutable to an expression.
Added a few missed files
Removed matrix element completely
Hid expressions within package
Put all functions in terms of Map
Expressed const operations in terms of others
Renamed AppendToSlice to Append
Added complex vector library

Split real vector functionality into transformable and otherwise.
Modified permissions of bash scripts
Moved ./ into vec/

Renamed One and Zero to Ones and Zeros to match Matlab.