Added new shell commands
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.
Added readme.md for komodo-shell describing how to build and run the shell.
Added clarification to readme
Lots of work around artifacts.
Upgraded to using s-ramp 0.1.0. Made the commands cancelable in the hope that the GUI could also use them.
Created a relationship on VdbArtifact so that it knows what its derived artifacts are. Refactored relationship
definitions to their specific artifact type.
Merge pull request #89 from elvisisking/artifact-command-sramp

Upgraded to S-RAMP 0.1.0. Created new artifact types for VDB objects. Made commands cancelable. Worked related to artifact relationships.