[illumos-Developer] [REVIEW] 224 findunref build shouldn't fail if SCM can't be determined

[Richard Lowe]

I'd like review for:
  224 findunref build shouldn't fail if SCM can't be determined

webrev:
  http://richlowe.net/webrevs/il_224

This causes bldenv, like nightly, to set SCM_TYPE to "none" if an SCM
recognized which_scm but not by anything else is detected.  The only
deviation here is that I let git pass through because I know that
stock which_scm doesn't ever return it it, but Joyent and others do
use it (with a fixed which_scm, and the rest of the stuff to do the
right thing).  I'm willing to remove git from the list if people feel
particularly strongly.

I've tested this in an (unrecognized) git repository without the hack
'exception_list.unknown' by doing a successful 'dmake setup'.

There're two unrelated changes in here, deleting commented code and
fixing an always-true condition (since the string "false" is just as
true as the string "true").

-- Rich