Merge pull request #6900
2cecb24 doc: change suite to trusty in gitian-building.md (Wladimir J. van der Laan)
957c0fd gitian: make windows build deterministic (Wladimir J. van der Laan)
2e31d74 gitian: use trusty for building (Wladimir J. van der Laan)
0b416c6 depends: qt PIDLIST_ABSOLUTE patch (Wladimir J. van der Laan)
9f251b7 devtools: add libraries for bitcoin-qt to symbol check (Wladimir J. van der Laan)