sci-mathematics/rstudio: Bump to 1.2.5033, use acct rstudio-server

sci-mathematics/rstudio: Bump to 1.2.5033, use acct rstudio-server

Thanks to John Dough for reporting the version bump bug #702140.

Thanks to toralf for reporting bug #693662.  The egit_clean: command not found
is fixed by inherit vcs-clean.

The QA: other
The ebuild is installing to one or more unexpected paths:

  /usr/extras

is fixed with the sed under this comment:
# install themes in /etc/rstudio/extra/sthemes instead of /usr/extra/themes

The: One or more CMake variables were not used by the project:
  QT_QMAKE_EXECUTABLE
  RSTUDIO_INSTALL_FREEDESKTOP

is fixed by only setting these variables if use !dedicated.

Thanks to Alessandro Barbieri reporting bug #696944, the dependencies are
unbundled in rstudio 1.2.5033.ebuild, and some needless dependencies are
removed.

Closes: https://bugs.gentoo.org/show_bug.cgi?id=702140
Closes: https://bugs.gentoo.org/show_bug.cgi?id=693662
Closes: https://bugs.gentoo.org/show_bug.cgi?id=696944
Package-Manager: Portage-2.3.84, Repoman-2.3.20
Signed-off-by: Mark Wright <gienah@gentoo.org>