This helps ensure that mismatched permission on `_bin_dir` and `_man_dir` don't cause issues.
Also prevents creating man pages owned by root being written to the user's $HOME
This adds support for serveral new command line options (taken from the usage):
- `-b, --bin-dir Override the bin installation directory`
- `-m, --man-dir Override the man installation directory`
- `-a, --arch Override the architecture identified by the installer`
- `-h, --help Display this help message`
This also (coincidentally) allows for $BIN_DIR, $MAN_DIR, and $ARCH to be set to create default settings for these.
These variables are *always* overwritten by the command line arguments.
aarondill
Ajeet D'Souza
Adam Stephens
Kartik Sharma