add option to supply more dependencies manually

[serhei]

May be useful when the executable requires additional files besides shared libraries. However, dependencies will be copied to the temporary folder -- so the tool must be configured to find them under /tmp/oc-inject-?. In some cases this could be configured by specifying environment variables via -D option (although we will have to have the -D option support a wildcard string that is replaced by the temporary folder oc-inject created).

[serhei]

May also help to add an option that provides additional search directories for ldd.