credential management: delete credential implemented

updated passkeez version

Merge pull request #11 from r4gus/keepassxc-integration-feature

prepared for 0.3.1

README.md updated

fixed bug in keylib that prevented the creation of credentials when u…

…sing firefox

install script updated

build script updated

keylib dep updated

keylib updated

the new trademarked logos look too familiar to mine so... time for a …

…new logo