Fix ticket:92

Type derivation for log fixed to be consistent with the actual
returned values.

 * src/compiler/float-tran.lisp:
   * Update {{{LOG-DERIVE-TYPE-AUX-1}}} to compute the correct type.

 * tests/trac.lisp:
   * Add test for trac ticket:92
Update from commit logs.
Fix ticket:87

Add {{{:ELEMENT-TYPE}}} keyword option to {{{RUN-PROGRAM}}}

 * src/code/run-program.lisp:
   * Add :element-type option, and use it as needed when creating
     input or output streams.

 * tests/trac.lisp:
   * Add tests.
Update from logs.
Fix path so (require :lisp-unit) actually loads.
Fix ticket 93.

 * src/code/reader.lisp:
   * Try to round really small numbers
   * Add somewhat more informative message when the number is not
     representable.
 * src/i18n/local/cmucl.pot:
   * Update
 * tests/trac.lisp:
   * Add test for ticket 93
   * Add a few comments for test trac.87.
Fix ticket 94.

 * Add least-positive-normalized-double-double-float,
   least-negative-normalized-double-double-float,
   least-positive-double-double-float,
   least-negative-double-double-float,
   most-positive-double-double-float,
   most-negative-double-double-float to the extensions package.
Update from recent changes.
Merge branch 'master' into rtoy-round-float-in-reader
Fix ticket 93.

 * Round the number to least-positive-foo-float when possible, but
   still throw an error if it's too small but not zero.
 * Update comments to mention CLHS 2.3.1.1.
Regenerated.
Regenerate.
Regenerated piglatin translation.
Update from commit logs.
Revert change for ticket 92.

It's incorrect. We really want log(-0) to be -inf + i*pi. It's needed
to get the correct values on the branch cuts of the special functions
from the definitions.  

Update trac test to test for this.
Add double-double-float-positive-infinity and
double-double-float-negative-infinity.
Return the correct values for (log -0w0) and (log 0w0).  Previously we
returned something like #c(-715 pi) and -715.

 * src/code/irrat-dd.lisp:
   * Handle -0w0 and 0w0 specially in dd-%log.

 * tests/trac.lisp:
   * Add a test for this in trac.lisp.
Add unicode tests, based on the tests in src/i18n/tests.
Remove these test files since they've been migrated to lisp-unit.
First cut at adding PCL tests.