HPCC-9415 Use epoll_wait instead of select

Signed-off-by: Mark Kelly <mark.kelly@lexisnexis.com>
HPCC-9415 Handle threads adding and removing fs properly

Signed-off-by: Mark Kelly <mark.kelly@lexisnexis.com>
HPCC-9415 Epoll new runtime implementation

Signed-off-by: Mark Kelly <mark.kelly@lexisnexis.com>
HPCC-9415 Epoll move add into updateItems so its more like original

Signed-off-by: Mark Kelly <mark.kelly@lexisnexis.com>
HPCC-9415 Testing code for epoll

Signed-off-by: Mark Kelly <mark.kelly@lexisnexis.com>
HPCC-9415 Epoll updates for performance

Signed-off-by: Mark Kelly <mark.kelly@lexisnexis.com>
HPCC-9415 Enable epoll use for all by default

Signed-off-by: Mark Kelly <mark.kelly@lexisnexis.com>