make line widths customizable
add missing index
making point size customizable per line as well
pointGrow and pointShrink must adapt to the point size position of the index
fix hilight WIP
Merge branch, and merge with previous changes.

Previous point-width work by other contributors conflicted, so have tied
the two changes and sets of tests together. Have also slightly changed
some variable / config names to read easier.

Merge branch 'master' of https://github.com/dgilperez/morris.js into dgilperez-master

Conflicts:
	lib/morris.line.coffee
	morris.js
	morris.min.js