Sparse notes on major existing problems/plans

* Re-design SMI model aiming at more consistent design
  and better performance. One problem with current model
  is that MIB variable and variable instance is not clarly
  separated. Scalar vars and table cells should share the
  same mechanics. For example, MibVariable may be a subtree
  with a single leaf -- MibVarInstance; MibColumn would also
  hold a ref to MibVarInstance then.

  Linear search for subtree constributes to poor performance,

  Possibly, MIB tree should be a single-level dictionary of
  MIB objects.

  Subtree registration at MIB tree objects may be obsolete

  Another issue showed up in MIBVIEW object model: MIB module name,
  MIB object name and object instance should be clearly separated.
  Dedicated, simple API for table cells mangling should be provided.
  The whole thing should be simpler, including API.

* Trap application code is still 90% finished. Also, examples & apps
  needed.

* At MibViewController, do not index intance objects

* Implement 'oneliner' API for v1arch

* Implement prettyIn value format parser at TC

* Disallow SNMP access to USM objects

* Make sure objects shutdown methods work alright

* Maybe MibInstrumentationController should be async what
  implies callback function interface.

* Re-work ACL to get rid of linear search there

* Implement SNMP trap and proxy apps; complete example apps

* Check for memory leaks esp. on failed requests

* Implement partial context name match at isAccessAllowed()

* Should managed objects be accessed through some dedicated,
  non-SNMP-based API? A sort of backdoor which is basically
  intrum minus transactions and AC.

* Clean up cache management code at MsgAndPduDsp and MP

* Sort out whether pyasn1 obejcts should probably have either clone() or 
  subtype() methods.

* Implement SNMP engine-scope debug mode logging

* Convert symbolic constants into integers for performance and typing
  reliablity

* Expire discovered snmpEngineIds at mpmod/rfc3412

* Implement by-transportTag search at secmod/rfc2576

* Review PDU components coercion code at proxy/rfc2576

* TextualConvention subclassing order now depends upon DisplayHint 
  clause presense in MIB definition (for useful prettyIn/Out()). Maybe 
  this should be re-worked.