Fix some typos, reformat some comments, add a missing header.
Remove old build/install instructions. Did not edit user guide.
Merge pull request #190 from chrisdembia/delete-some-old-install-instructions

Remove old build/install instructions. Did not edit user guide.
Fix UNIX bash path-setting commands.

See discussion in issue #50.
Merge pull request #191 from chrisdembia/fix-README-bash-instructs

Fix UNIX bash path-setting commands.
Fix most warnings generated from -Wmost, for SimTKcommon.
Fix travis syntax error.
Fix clang SimTKcommon warnings; use -Wall in travis.
Remove pragma to avoid MSVC bug.
Minor comment changes.
Define time conversion when using MSVC.
Fix TestPlugin test failure; updating cwd.
Fix Wstrict-aliasing in String.
Ignore -Wmaybe-uninitialized in rpoly.
Clean up GCC pragmas in rpoly.
Hide GCC pragmas when using clang.
Fix Pathname GCC/Clang warning.
rpoly GCC warning is gcc-version-dependent.
Fix silly preprocessor typo.
Undefine a temporary preproc. def.