Fix segfault when aug_init/close are called multiple times
Fix segfault when aug_init/close are called multiple times

The way we cached the regexp '[0-9]+/' was totally botched. We now allocate
the pattern statically in memory and pin it to protect it from being freed,
ever.

Reported by Harald Hoyer

hercules-team/augeas-do-not-use,manandbytes/augeas,kumy/augeas,ptoscano/augeas,jasperla/augeas,jasperla/augeas,GeoffWilliams/augeas,dafugg/augeas,domcleal/augeas,hercules-team/augeas,bkearney/augeas,jjlin/augeas,bkearney/augeas,kumy/augeas,kunkku/augeas,mchf/augeas,bkearney/augeas,pevalme/augeas,mlichvar/augeas,hercules-team/augeas,lutter/augeas,manandbytes/augeas,mlichvar/augeas,pevalme/augeas,domcleal/augeas,raphink/augeas,GeoffWilliams/augeas,jtopjian/augeas,camptocamp/augeas,jjlin/augeas,kunkku/augeas,pevalme/augeas,ptoscano/augeas,jtopjian/augeas,lutter/augeas,raphink/augeas,mchf/augeas,camptocamp/augeas,MikaelSmith/augeas,lutter/augeas,kunkku/augeas,kumy/augeas,camptocamp/augeas,mlichvar/augeas,kumy/augeas,ptoscano/augeas,hercules-team/augeas-do-not-use,hercules-team/augeas-do-not-use,dafugg/augeas,MikaelSmith/augeas,domcleal/augeas,camptocamp/augeas,dafugg/augeas,bkearney/augeas,jjlin/augeas