Added ability to check if a word is in a dictionary
Added ability to check if a word is in a dictionary


Former-commit-id: 9bb015a97755e32914165dc084b821cbd2b7cd46
clab/dynet,shuheik/dynet,chunyang-wen/dynet,clab/dynet,clab/dynet,clab/cnn,danielhers/dynet,xunzhang/dynet,shuheik/dynet,shuheik/dynet,shuheik/dynet,danielhers/dynet,clab/dynet,xunzhang/dynet,shuheik/dynet,xunzhang/dynet,danielhers/dynet,clab/cnn,danielhers/dynet,xunzhang/dynet,shuheik/dynet,danielhers/dynet,chunyang-wen/dynet,shuheik/dynet,clab/dynet,clab/dynet,chunyang-wen/dynet,clab/cnn,chunyang-wen/dynet,clab/dynet,danielhers/dynet,danielhers/dynet