[lmi] Output improvements

[Greg Chicares]

I've made various improvements to the html calculation summary
and to some copy-to-clipboard and emit-spreadsheet facilities.

Here are some new command-line options for testing these changes.

  --pyx='old'

Use the old behaviors instead of the new, for all these changes.

  --pyx='both'

Show both the old and the new calculation summary together.

  --pyx='both write'

Like 'both', but also write both calculation summaries separately
to these files:
  /opt/lmi/bin/xsl.html [old xsl calculation summary]
  /opt/lmi/bin/cpp.html [new C++ calculation summary]
which can be examined in any html browser.

Here are some timing data.

milliseconds for html with a full set of columns, no solve, VUL:
  calculate format total
      80      350   430   old
      70       60   130   new

milliseconds for "Illustration | Copy full illustration data":
            format
             1000         old
               26         new

The calculation summary's alignment is improved. Some columns
don't yet work and might even fail spectacularly; that's what I'm
currently working on.

Policy number now appears in the result of
  "Census | Print case to spreadsheet"
and also
  "Illustration | Copy full illustration data"
The latter now uses the same code as the former:
 - no longer are the results gratuitously different
 - greater precision
 - also creates spreadsheet file
 - did I mention that it's noticeably faster?