Bug fixes & build improvements

• Add optional team argument to team_number() thanks to @nathanweeks
• Fix installer issues including:
  • #629: problems in environment setup script
  • #635: caf wrapper script can't be used for shared libs since it defaults
    to linking in libcaf_mpi.a which is compiled w/o -fPIC; now
    position independent code (PIC) is used for the static lib too
  • Fix for binary installs of CMake if sudo is needed
  • Bump default GCC/GFortran to 8.3
  • Fix for the minimum compiler version compatibility check
• Reduce potential module file name clashes with other software by adopting
  a prefix, e.g., assertions --> oc_assertions

Installation

Please see the installation instructions for more details on how to build and install this version of OpenCoarrays

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