Upgrade qulice to 0.18

[krzyk]

There have been few changes in it (so it might be easier to do upgrade in steps -> 0.17.5, 0.17.6, 0.18):

• removal of AvoidInstantiatingObjectsInLoops (so each suppression of that should be removed)
• add of EmptyLinesCheck (each class member should have a single line between itself and another class member) - No check to ensure empty lines are present where needed qulice#576
• threaded checkstyle and PMD execution (should speed up qulice for larger projects)
• fixes in ProtectedMethodInFinalClassCheck (suppresions might be not needed - Should ProtectedMethodInFinalClass really exist? qulice#901)
• new Checkstyle (8.11) and PMD (6.6.0) version - fixes for checks

[0crat]

@llorllale/z please, pay attention to this issue

[0crat]

@krzyk/z this project will fix the problem faster if you donate a few dollars to it; just click here and pay via Stripe, it's very fast, convenient and appreciated; thanks a lot!

[llorllale]

@krzyk I'm going to delay doing this until some future point past the 1.0 release

[0crat]

Job gh:yegor256/cactoos#946 is not assigned, can't get performer

[0crat]

This job is not in scope