Fixed bugs with property key lookups and variable variables
Extracted generic string-interpolate.js library
Squashed 'lib/string.interpolate.js/' content from commit bd62000

git-subtree-dir: lib/string.interpolate.js
git-subtree-split: bd6200007aa41ced474a5943f7df4510ea13e717
Merge commit '01df8ec717b0b6c790a3be75aa0d96f78ea96568' as 'lib/string.interpolate.js'
Added build process using external string.interpolate.js library