Sell screen outline ready
Sell screen advnacments
Sell Screen Ready
Added toast to sell screen
Fixed listing multiple authors
Merge remote-tracking branch 'origin/sellScreen-Branch'
Merge branch 'master' of https://github.com/CS275Group1/cs275.bookswap
BookDetails formatting
Implemented email seller
Changed buy_screen_edit_hint
more work
Merge branch 'master' of https://github.com/CS275Group1/cs275.bookswap

Conflicts:
	AndroidManifest.xml
	gen/com/bookswap/cs275/R.java
	res/values/strings.xml
	src/cs275/bookswap/MainScreen.java
fixed email to use correct dynamic addresses
added FindISBNForUserTask to prevent duplicate listings

returns true if a book of a given isbn10 was listed by a user.