Improve parsing of 'expr' query terms
Improve parsing of 'expr' query terms

Fixes #157 / 9DF85DF2-4BF5-4931-A30C-2592A10BB5C0

paulbdavis/ledger,paulbdavis/ledger,ledger/ledger,jwakely/ledger,ledger/ledger,jwakely/ledger,jwakely/ledger,ledger/ledger,duncanmortimer/ledger,ledger/ledger,paulbdavis/ledger,ledger/ledger,afh/ledger,paulbdavis/ledger,jwakely/ledger,paulbdavis/ledger,paulbdavis/ledger,afh/ledger,duncanmortimer/ledger,duncanmortimer/ledger,afh/ledger,duncanmortimer/ledger,paulbdavis/ledger,jwakely/ledger,duncanmortimer/ledger,jwakely/ledger,duncanmortimer/ledger,afh/ledger,jwakely/ledger,duncanmortimer/ledger,afh/ledger