Fix broken command line in the `Makefile`.

The argument including ';' should be quoted because the it will be
interpreted as the end of the line by the ordinary UNIX shells.
Merge pull request #186 from yyuu/semi-colon

Fix broken command line in the `Makefile`.
https://ironruby.codeplex.com/workitem/7406

Added default constructor for Encoding (mainly for Marshal.load).