Experimental support for Fortran 2015 teams (20170912)

This release contains experimental support for the teams feature described in the draft Fortran 2015 standard. This release is based on GCC commits through 9 September 2017, which include the recently committed gfortran support for

• The last previously unsupported Fortran 95 feature and
• The last previously unsupported Fortran 2003 feature

With the additional support this release provides for teams, gfortran is approaching full Fortran 2015 compliance, notwithstanding bugs, some partially supported major features, and a few unsupported minor features.

Experimental support for Fortran 2015 teams (20170830)

Merge pull request #3 from sourceryinstitute/master

update teams branch from upstream