Merge pull request #2 from omarshaik/feature/omar/lineChart

Feature/omar/line chart
add couple delegate methods. trying to match methods to user stories
set up background of graph
draw x and y axes
renamed delegate methods to mimic Jawbone
add gridlines
add switch button for gridlines
put gridlines in array and display the array instead of display gridline one by one
create axesView and add gridlines as subLayers to axes view
Merge pull request #3 from omarshaik/experimental/john/tryMakeLineGraph

Experimental/john/try make line graph
add dynamic y-axis that is benchmarked by highest value data point
clean up some code
Merge pull request #4 from omarshaik/feature/plotPointsOnGraph

Feature/plot points on graph
Move GraphView into project directory from top-level directory.
Add initial setup code in base class, GraphView.
Begin implementing LineGraphDataSource.
Refactor how gridlines are displayed and hidden.