portfolio object created

Basic portfolio and several initial methods created.
Merge branch 'portfolio'
some random code stubs
account-portfolio-asset communication
Merge pull request #7 from merkhofer/master

account-portfolio-asset communication
some random code stubs
added more stuff to get all the base linkages working
Merge remote-tracking branch 'origin/updates_portfolio' into updates_portfolio

Conflicts:
	asset.rb
	portfolio.rb
Merge pull request #3 from skunath/updates_portfolio

Updates portfolio