editor: remove superfluous waitForReadyRead

We already wait if we fail on the first getChar()-call, so there's
no point in doing this here.
editor: use QByteArray instead of std::string

While we're at it, clean up some cruft.
Bugfix TrackView::editPaste() to not read data from a dead object

mimeData->data(...) returns a QByteArray. Previously this object was
not stored anywhere, but instead a pointer to this array's raw data was
obtained. As the returned QByteArray was destructed immediately after
the pointer was fetched, the clipbuf pointer started to point to
an unused memory area. This caused paste to crash when the memory area
was overwritten by other parts of the program and garbage CopyEntry
objects were read.
Merge pull request #7 from anttihirvonen/paste-crash-fix

Bugfix TrackView::editPaste() to not read data from a dead object
editor: use QVector rather than std::vector

Using the same implementation on all platforms leads to less
platform-surprises.
editor: use QByteArray for WebSocket buffer

Instead of using std::string, let's use QByteArray. While we're at
it, change some size_t's to int to avoid casts.
editor: use qMin/qMax/qBound
editor: use QByteArrays for WebSocket upgrade
editor: QString for track-names
editor: fixup a cast
editor: use QMap for clientTracks
editor: use Q_ASSERT instead of assert
editor: remove needless includes

Now we only depend on Qt for the editor. No standard-lib includes
at all.
editor: add missing include-guard
editor: prefer standard header-guards

Pragmas are language extensions, so let's not depend on them. Use
"normal" header-guards instead.
editor: paint utf-8 track-names properly
player: close socket on handshake-mismatch