[local-time-announce] New local-time release 0.9.3

[Daniel Lowe]

The newest release of the local-time library has arrived.  Please note that we
are going to be drastically changing the API for a 1.0 release available soon.
This 1.0 release will have a guaranteed stable API until the next major version
number.

This release introduces some incompatible changes:


  - added adjust-local-time, and adjust-local-time! (which sideeffects the
    changes into the input).

    example uses:

    (adjust-local-time sunday (offset :day-of-week :monday))
    (adjust-local-time epoch (set :timezone to utc-1))
    (adjust-local-time sunday (offset :day by 3))

    "to" and "by" is optional and otherwise is ignored.
  - MODIFIED-LOCAL-TIME and ADJUSTED-LOCAL-TIME has been merged into
    ADJUST-LOCAL-TIME
  - the non-exported LOCAL-TIME-SUM has been dropped

Other updates are:


  * fix Gregorian leap year rules: 100 and 400 years rules were not taken
    into account which broke timestamps when using cl-postgres and year far
    enough from now.
  * Added texinfo doc
  * support overflow on nsec value in encode-local-time
  * Optimized format-timestring
  * Fixed nsec parsing on 32-bit systems
  * Added decode/parse/encode durations in the form of ww-ddThh:mm:ss.sss
  * Added function clone-local-time
  * Eliminated confusing local-time-diff. Added local-time+ and local-time- and
    encode-duration. Durations are represented in seconds.

Thanks to Attila Lendvai and Levente Meszaros for their help!

: Daniel :