initial version from Jan Holst Jensen
minor updates
add to python wrapper
add some tests; add radicals to output
get rgroups working
a few more tests and a fix to not print empty bond blocks
fix isotope handling in V3K
get atom lists working
support forcing V3000 writing and kekulization in the SDWriter
Fixes #174
add tests for the kekulize and forceV3000 options
a couple more tweaks from Jan
add (non-standard) handling of R groups to v3k mol parser
more isotope fixing
further R group handling
Fixes #187
Fixes #186
Fixes #191
Merge branch 'Issue194_V3000MolWriter'

Conflicts:
	Code/GraphMol/Chirality.cpp
	Code/GraphMol/FileParsers/test1.cpp