Add missing conflicts

[dmoody256]

This change adds conflicts for most of the packages to help create saner environments. The problem is that all the versions need to symlink their binaries to the the same location, which means there is an actual conflict. Labeling the conflict in the formulae makes homebrew print the correct advice to unlink conflicting packages before trying to install a new version.

Otherwise it will just print more ambiguous error messages that the current package could not complete the symlink because the symlink already exists (although it is pointing to a different existing installed versions). Some of the packages use keg_only to deal with this, but that creates ambiguity around what version is being used, as the service only runs the one linked, not the keg_only ones.

This change also removes the EOL 4.4 versions.