Cache semver() output in .mkit/semver

src/include/facts.sh

     local commit        # commit indicator (CURRENT_BRANCH.gHASH)
     local dirty         # 0 if dirty, 1 if clean
     local suffix        # version suffix
+    local_get semver && return 0
     version=$(ini 1value project:version)
     prerl=$(ini 1value project:prerl)
     grep ":" <<<"$prerl" \
         test -n "$prerl" && suffix="-$prerl$suffix"
         version="$version$suffix"
     fi
+    local_putb semver <<<"$version"
     echo "$version"
 }