feat(astf): Support framesizes for ASTF

feat(astf): Support framesizes for ASTF

- No support for IMIX.
+ Fix a bad bug in padding (most ASTF profiles had wrong frame sizes).
+ Fix a big typo in TCP PPS profiles (s->c was not data, just RST).
+ Control transaction size via ASTF_N_DATA_FRAMES env variable.
 - Default value 5 leads to transactions smaller than before.
 + It ensures transaction is one burst (per direction) even for jumbo.
+ Edit autogen to set supported frame sizes based on suite id.
 + Both TCP and UDP use the same values:
  + 64B for CPS (exact for UDP, nominal for TCP).
  + 100B, 1518B and 9000B for TPUT and PPS.
   - TCP TPUT achievable minimum is 70B.
   + Used 100B to leave room for possible IPv6 ASTF tests.
 + Separate function for code reused by vpp and trex tests.
 - I do not really like the new "copy and edit" approach added here.
  + But it is a quick edit, better autogen refactor is low priority.
+ Consider both established and transitory sessions as valid.
 - Mostly for compatibility with 2202 behavior and to avoid ramp-ups.
 - Assuming both session states have similar enough VPP CPU overhead.
 + Added a TODO to investigate and maybe reconsider later.
+ Update the state timeout value to 240s.
 + That is the default for TCP (for transitory state).
 - UDP could keep using 300s.
  + But I prefer UDP and TCP to behave as similarly as possible.
+ Use TRex tunables to get the exact frame size (for data packets).
 - It is not clear why the recipe for MSS has to be this complicated.
 + Move code away from profile init, as frame size is not known there.
 + Change internal profile API, so values related to MSS are passed.
+ Lower ramp-up rate for TCP TPUT tests.
 + Because without lower rate, jumbo fails on packet loss in ramp-up.
 + UDP TPUT ramp-up rate also lowered (just to keep suites more similar).
+ Distinguish one-direction and aggregated average frame size.
 + Update keyword documentation where the distiction matters.
 + One-direction is needed for turning bandwidth limit to TPS limit.
 + Aggregated is needed for correct NDRPDR bandwidth result value.
 - TCP TPUT will always be few percent below bidirectional maximum.
  + That is unavoidable, as one direction sends more control packets.
+ Add runtime consistency checks so future refactors are safer.
 + Fail if padding requested would be negative.
 + Fail if suite claims unexpected values for packets per transaction.
+ Edit the 4 types of ASTF profiles to keep them similar to each other.
 + Move UDP TPUT limit value from a field back to direct argument.
 + Stop pretending first UDP packet is not data.
+ Apply small improvements where convenient.
 + Replace "aggregate" with "aggregated" where possible.
  + To lower probability of any future typos in variable names.
 + Avoid calling Set Numeric Frame Sizes twice.
 + Code formatting, keyword documentation, code comments, ...
 + Add TODOs for less important code quality improvements.
- Postpone updating of methodology pages to a subsequent change.

Change-Id: I4b381e5210e69669f972326202fdcc5a2c9c923b
Signed-off-by: Vratko Polak <vrpolak@cisco.com>