Initial commit
Initial version of starter code
Added design document
Completed the Design Document
Added more clarification on the interactions with jbox2d in the
DesignDocument.
Added some minor revisions to the design document based on extra information about how muscles function
Added extra method for Muscles on design document
Typo on design document fixed
Added basic implementation of the FixedMass class and removed the add new
ball button.
Committed design document changes to resolve apparent merge conflict.
Merge branch 'master' of https://github.com/duke-compsci308-spring2014/springies_team26

Conflicts:
	DesignDocument
Modified constructor parameters for FixedMass and overrode move() method.
Modified FixedMass constructor to use default mass instead.
Implemented a Mass object.
Added initial XML reading
Merge branch 'master' of http://github.com/duke-compsci308-spring2014/springies_team26
Added mass creation to XML reading
Committed changes to fixedmass for pull.
Merge branch 'master' of https://github.com/duke-compsci308-spring2014/springies_team26
Made the FixedMass class do what it's supposed to.