Merge pull request #19 from abrisse/master

Support of session parameters + Add the #size method
ensure specs run against AllegroGraph version 4.3.3
some refactorings
removed test file
added travis-ci build matrix
added Gemfile
added build status to readme
updated readme
updated Gemfile
fixed rakefile
Merge branch 'upmaster'

Conflicts:
	lib/allegro_graph/repository.rb