sbcl-1.5.4 released

Dear all,

The release artifacts for are now on SourceForge, and the git repository
has the tag: the sbcl-1.5.4 release is done!  Major changes are
summarized (summerized?  It's hot here!) below.

Best wishes,

Christophe

changes in sbcl-1.5.4 relative to sbcl-1.5.3:
  * minor incompatible change: hash tables on 64-bit machines consume roughly
    20% less memory but can only grow to hold 2^31 entries (theoretically)
    due to use of 31-bit indices internally.
  * platform support:
    - RISC-V: improve rotate-byte support (thanks to Philipp Matthias
      Schaefer)
  * bug fix: the system reasons more correctly regarding the array rank of
    complicated array types.  (reported by Bart Botta)
  * bug fix: DOUBLE-FLOAT-P never gets weaked to NUMBERP.  (reported by Bart
    Botta)  
  * enhancement: the regression test suite can now benefit from paralellism,
    completing much faster when enough compute power is available.
  * optimization: readtables with non-base-char dispatch characters are less
    inefficient.
  * optimization: INTERN performs fewer redundant type checks.
  * optimization: tests for PATHNAMEP and STRUCTURE-OBJECT (including in
    computing hash functions) are faster.