Fixed issue that minecraft's recreates the logfile on server start,
making tailing the log just hang without new output.
Added additional regex to identify log entries in the new 1.7 format
Fixed log_line_get_time: It now verifies the format of the log line
before extracting the time. Note that the new logging format only has a
timestamp without date component, which may cause trouble!
Fixed server_log_dots_for_lines and server_log_get_line:
They now return immediately on encountering the pattern (param $3)
regardless of whether log-format is pre-1.7 or 1.7, rather than waiting
until the timeout occurs.