Update author's credits comments for wxQT

Commit history was lost in the git to svn merge for trunk, so this reflect work done in two GSOC projects and/or by several authors.
Lines changed by each user was the main metric used to ack major contributions.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@77497 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775