Change the order of initialization to have this plugin first

[frederickjh]

As mention in xxh/xxh#76 in commit xxh/xxh-shell-fish@3ba8be81 the feature was added to allow changing the the order of initialization of the pluginrc.* files. See this comment for details.

Because this plugin allow the user to copy user configuration to the remote host that may be needed for other plugins like package managers it should be initialized before them so that the configuration is in place. Currently the Fisher plugin installs package on the second time login in because then it finds the configuration files that were not there the first time it ran.