Fix parsing of floats with no fractional part

For example: "1." is allowed by Lua but was not recognised by dokx
Downgrade warning for unexpected namespaces

Changed to 'info' level, since it can suffer from false positives
Use logroll instead of lualogging

This avoids an extraneous 'changing log level' message. The libraries
are otherwise very similar, although all of the log calls have to be
changed since they are no longer methods.