localize sdf to a single definition
make conses thread safe
add javadoc
fix failure to report errors
fix Radu's comment
Merge pull request #1123 from dwightguth/kem

fix failure to report errors
Merge pull request #1119 from dwightguth/conses

make conses thread safe
Merge pull request #1118 from dwightguth/localsdf

localize sdf to a single definition