Changed the logging mechanism

After profiling, the regex library for logging was consuming way to
much time. I changed it to a simple {name, id} match filter.
Finished removing RE2 library.

The RE2 regex library turned out to be a bad choice for the logging
filter system. The recent change consumes much less time:
RE2= 34s
New= 7s

Further profiling should be done to determine if the logging consumes
too much time.
Lint cleanup
Added lib/json and lib/zlib
Added src/settings for using settings files.