Check for $HOME/Applications/MacVim

homebrew creates a link for the current version of MacVim in
$HOME/Applications rather than checking if there is a specific version
in /usr/local/Cellar, use the current version in $HOME/Applications.
Change MANPAGER to vi -R

On some linux systems view throws error messages with settings in the
vimrc, causing me to remove the MANPAGER setting all together. Rather
than doing that, switching from view to vi -R which doesn't have the
problem.