Updated icons of movers.
Revised expansion vessel for #193.
Changeg icon for #193.
Changeg icon for #193.
Updated documentation for new expansion vessel.

This is for #193. This change also corrects the image width through the css file.
Merge pull request #204 from lbl-srg/issue193_expansionVessel

Issue193 expansion vessel
Merge pull request #207 from lbl-srg/master

Merge expansion vessel to valve branch.