JoplinS/search: convert-ly to 2.18
JoplinS/search: order indentation and remove trailing white spaces
JoplinS/search: add source header and few changes.

I've adjusted some slurs and stem directions according to the
source available on IMSLP:
http://imslp.org/wiki/Searchlight_Rag_(Joplin,_Scott)
Merge branch 'search-light-rag' of https://github.com/fedelibre/The-Mutopia-Project
Header tweaks to match previous metadata