Addes some constants for the default s-ramp artifact properties. These constants can be used in queries. Also started trying to my
the maven modules osgi compatible.
Refactoring of shell packages. Created shell command test framework and tests. Fixed RepositoryManager query method so that it returns a QueryResultSet now.
Merge pull request #88 from elvisisking/shell-commands-misc

Refactoring of komodo-shell packages. Created shell command test framework and tests.