switch to mainline iipc webarchive-commons latest release
replace use of method removed from guava library
replace use of another method removed in updated guava library
webarchive-commons 1.1.4 has been released, bump dependency
Merge pull request #84 from nlevitt/iipc-webarchive-commons

switch to mainline iipc webarchive-commons latest release (1.1.4)