- return the library basename without leading 'lib' or trailing '.so'

- syntax as per Bourne/Korn shell
      ${parameter:-defValue}

  If parameter is unset or null, the \c defValue is substituted.
  Otherwise, the value of parameter is substituted.

- eg,
       "$USER $(PWD) $USER"  ->  "username $(PWD) $USER"
  instead of
       "$USER $(PWD) $USER"  ->  "username $(PWD) username"

  this is noticable in some dynamicCode usages

STYLE: consolidate all string expand code into stringOps

This reverts commit 98f269ed.