nfct: fix icmp type and code output key size
temporal commit
icmp pack filter: add new filter

This filter creates ICMP_TYPE Netfilter v9 from IPFIX icmpTypeIPv4
and icmpCodeIPv4.
time conversion filter: add new filter

This filter creates IPFIX_flow(Start|End)MicroSeconds and
IPFIX_flow(Start|End)SysUpTime from "flow.(start|end).sec" and
"flow.(start|end).usec".
Revert "nfct: add new output time keys"

This reverts commit ef7c29de09b63d9f1c6bb83daa2fb56bd0904f02.
add new filter instead of change nfct input
Revert "nfct: introduce new out key for ipfix timestamp"

This reverts commit 76818ff91bfc1640260d2c1d8106e0119d808366.
add new filter instead of change nfct input