Set execute permission on scripts with shebangs

[ellert]

• Set execute permission on scripts with shebangs

Checklist

• Code compiles correctly
• R CMD check still passes all tests
• Preferably, new tests were added which fail without the change
• Document the changes by file in ChangeLog

[eddelbuettel]

We tend not do the bulk whitespace change commits as they obfuscate git glame and friends. Please take the two files inst/tinytest/cpp/*cpp out of the PR (as well as src/Makevars.win), I can then accept the (fairly meaningless for very old examples) chmod part. In other words just exclude whitespace only changes.

[eddelbuettel]

Looks good to me. I am indifferent on the overall merit but it won't do harm.

[Enchufa2]

RPM packaging complains about executables without shebang and shebangs without execution bit. So this just makes life downstream easier. :)

[eddelbuettel]

I know, but it is still just a source property that has not bitten anyone in 15 years. Oh well. In it goes with dual approval.