- further cleanup of spec file.
Removed unneeded explicit Requires for
libcairo2/libfreetype6/liblzma5/libreadline6
Removed removal of backup file that was meanwhile removed upstream.

Thx to Jan Engelhardt, again!

- clean up of spec file after comments from Jan Engelhardt in
https://build.opensuse.org/request/show/393426
Some unneeded explicit BuildRequires removed.

- tre.patch was removed.

- and libbz2-devel needed, too.

- added BuildRequires: bzip2
for i586.

- upstream release 3.3.0
CHANGES IN R 3.3.0:
SIGNIFICANT USER-VISIBLE CHANGES:
* nchar(x, *)'s argument keepNA governing how the result for NAs in
x is determined, gets a new default keepNA = NA which returns NA
where x is NA, except for type = "width" which still returns 2,
the formatting / printing width of NA.
* All builds have support for https: URLs in the default methods
for download.file(), url() and code making use of them.
Unfortunately that cannot guarantee that any particular https:
URL can be accessed. For example, server and client have to
successfully negotiate a cryptographic protocol (TLS/SSL, ...)