Merge pull request Tribler#2752 from devos50/various_fixes_tribler7

WIP: various fixes for Tribler 7

Merge pull request Tribler#2716 from devos50/fixed_tftp_test

Fixed tftp test, improved piece drawing algorithm, improved support for older Twisted versions, fixed TunnelExitSocket error

Merge pull request Tribler#2153 from devos50/qt-gui

New Tribler PyQt GUI

New tag

Tribler 7.0, experimental release 1

Merge pull request Tribler#2498 from pimveldhuisen/add-libnacl-debian

Add libnacl as a dependency in the debian packager

Merge pull request Tribler#2220 from devos50/fix_builder_osx

Removed readme from OS X builder

Merge pull request Tribler#2205 from whirm/set_version_6.5.2

Update release info to 6.5.2

Merge pull request Tribler#2037 from whirm/version_change_6.5.1

Update version to 6.5.1

Merge pull request Tribler#1946 from whirm/6.5-version-change

Set version to 6.5