memory leak from lua regexps

[niq]

PCRE cpatt is compiled but never freed. Unfortunately the traceback is incomplete: only pcre.c and matcher.c are informative.

==1888== 142 bytes in 2 blocks are definitely lost in loss record 1,901 of 2,307
==1888== at 0x4C26FDE: malloc (vg_replace_malloc.c:236)
==1888== by 0x4E40C3A: ink_malloc (in /usr/lib64/libtsutil.so.3.0.0)
==1888== by 0x58B89E1: pcre_compile2 (in /lib64/libpcre.so.0.0.1)
==1888== by 0xEE62B16: modpcre_compile (pcre.c:95)
==1888== by 0xE84B55F: ib_matcher_compile (matcher.c:113)
==1888== by 0xFEEC290: lj_vm_ffi_call (in /usr/local/ironbee/lib/ibmod_lua.so

[ironbee]

With major recent changes to mpool code all mem leaks will be investigated as a task