Expanded the spin ID list for the structure.load_spins user function.
This now includes the spins "@N", "@NE1", "@C", "@H", "@O", "@P", ":A@...", ":A@...", ":G@...", ":G@...", ":C@...", ":C@...", ":U@...", ":U@...", ":U@...".
Authored by: bugman 2012-09-17
Parent: [r17484]
Child: [r17486]
