Allow to restrict usage of wildcard imports

[skuzzle]

As wildcard imports may lead to inaccurate results, we could implement a flag that will cause the analysis to fail if one is encountered.

Wildcard imports can be considered a bad practice, so this might be a helpful feature anyway

[skuzzle]

The special literal package part '*' can be used to match only wildcard imports:

Preventing a certain wildcarad import:

<bannedImport>java.util.'*'</bannedImport>

This pattern will prevent the usage of wildcard imports from java.util while still allowing explicit imports like java.util.ArrayList

Preventing any wildcard import:

<bannedImport>**.'*'</bannedImport>

[skuzzle]

Will be released as 0.18.0