For the case of Clojure and other Lisp syntax highlighting, it is
necessary to create huge regexps consisting of hundreds of symbols with
the pipe (|) character. To make things more difficult, these Lisp
symbols sometimes consists of special characters that are themselves
part of special regexp characters like '*'. In addition to being
difficult to maintain, it's performance is suboptimal.
This patch introduces a new predicate to perform 'source' matching in
amortized constant time. This is accomplished by compiling a hash table
on the first use.
Add support for default start and end row when omitted in the
query:iter_captures and query:iter_matches functions.
When the start and end row values are omitted, the values of the given
node is used. The end row value is incremented by 1 to include the node end
row in the match.
Updated tests and docs accordingly.
