Issue 455 install.sh fix for CentOS 6

[zbeekman]

Avg response time	coverage on master

Summary of changes

Fixed typo triggered when MPI missing in CMakeLists.txt, fixed stack.sh functionality on bash 4.1, and partially fixed installing GCC prereqs on CentOS 6.

Rationale for changes

stack.sh failing with bash 4.1, typo in CMakeListsts.txt, some utils (yacc) don't accept --version

Additional info and certifications

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• Bug fix
• Feature addition
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[codecov]

Codecov Report

Merging #456 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #456   +/-   ##
=======================================
  Coverage   35.29%   35.29%           
=======================================
  Files           3        3           
  Lines        2105     2105           
  Branches      350      350           
=======================================
  Hits          743      743           
  Misses       1154     1154           
  Partials      208      208

[zbeekman]

Need to fix bad curl url on CentOS 6... curl doesn't like ftp://my.server.org:/path/to/file and I don't think it will resolve the host. Decent chance removing the second colon fixes the problem, may need to remove the ftp:// too.

@rouson do you know which systems need the ftp capability? If we changed the URL to be a sane one, then curl and wget would have a better shot at actually fetching gcc and prereqs.

[zbeekman]

LGTM

outstanding issues (ftp url with curl on CentOS6) remain, but this is a step in the right direction