Merge pull request #642 in SNORT/snort3 from appid_log_file_bug to master

Merge pull request #642 in SNORT/snort3 from appid_log_file_bug to master

Squashed commit of the following:

commit d75835a1383c4d93e68a8f32d135b693dbfe3d9a
Author: davis mcpherson <davmcphe.cisco.com>
Date:   Tue Sep 27 16:26:08 2016 -0400

    only log unknow appid if it is non-zero

    fix snort2lua to output 'log_stats true' for appid 'app_stats_filename' option'

    init static thread local variable for client app config

    fix issues from code review comments, u_int8_t->uint8_t, type/var/field renames to conform to coding style

    fix coding style naming issue