Added solid targets based on docdb 1464v3

[JamesShirk]

1. Changed target ladder to add in the thick carbon targets and aluminum targets
2. Add in new target macros for running with each of the newly added targets
3. Remove the old target macros based on the previously implemented targets
4. Rename one of the runexample macros that used the old targets and modify it to use the new targets

DocDB 1464 discussing the solid targets
DocDB 1537 showing slides about the implementation of the solid targets

targets, as implemented are now:

1. DS 2mm hole
2. DS Al 6 mm thick
3. DS Al 12.5 mm thick
4. DS C 40 mm thick
5. US C 2 mm thick
6. US 2mm hole
7. US Al 1 mm thick
8. US Al 2mm thick
9. Optics 1 (US C 254 um thick)
10. Optics 2 (DS C 254 um thick)
11. Optics 3 (MS C 254 um thick)

currently there is no "empty" target.