added support for configuration files in the following locations: (2), …

…fixes gpakosz#630

- ~/.tmux.conf and ~/.tmux.conf.local
- $XDG_CONFIG_HOME/tmux/tmux.conf and $XDG_CONFIG_HOME/tmux/tmux.conf.local
- ~/.config/tmux/tmux.conf and ~/.config/tmux/tmux.conf.local

fixed TMUX_PLUGIN_MANAGER_PATH when installed in ~

also made TMUX_PLUGIN_MANAGER_PATH available in the environment of the first created pane

.tmux.conf

@@ -1426,7 +1426,9 @@ run 'cut -c3- "$TMUX_CONF" | sh -s _apply_configuration'
 #   tmux_conf_update_plugins_on_reload="$3"
 #   tmux_conf_uninstall_plugins_on_reload="$4"
 #
-#   TMUX_PLUGIN_MANAGER_PATH=${TMUX_PLUGIN_MANAGER_PATH:-$(dirname "$TMUX_CONF")/plugins}
+#   if [ -z "$TMUX_PLUGIN_MANAGER_PATH" ]; then
+#     return 255
+#   fi
 #   mkdir -p "$TMUX_PLUGIN_MANAGER_PATH"
 #
 #   tpm_plugins=$(tmux show -gvq '@tpm_plugins' 2>/dev/null)
@@ -1459,7 +1461,6 @@ run 'cut -c3- "$TMUX_CONF" | sh -s _apply_configuration'
 #                               ;s/(install_plugin(.(?!&))*)\n(\s+)done/\1&\n\3done\n\3wait/g' "$TMUX_PLUGIN_MANAGER_PATH/tpm/scripts/install_plugins.sh"
 #           perl -p -i -e 's/git submodule update --init --recursive(?!\s+--depth\s+1)/git submodule update --init --recursive --depth 1/g' "$TMUX_PLUGIN_MANAGER_PATH/tpm/scripts/update_plugin.sh"
 #           perl -p -i -e 's,\$tmux_file\s+>/dev/null\s+2>\&1,$& || { tmux display "Plugin \$(basename \${plugin_path}) failed" && false; },' "$TMUX_PLUGIN_MANAGER_PATH/tpm/scripts/source_plugins.sh"
-#           tmux set-environment -g TMUX_PLUGIN_MANAGER_PATH "$TMUX_PLUGIN_MANAGER_PATH"
 #         fi
 #         if [ "$update_tpm" = "true" ]; then
 #           {
@@ -1502,7 +1503,19 @@ run 'cut -c3- "$TMUX_CONF" | sh -s _apply_configuration'
 #   tmux_conf_update_plugins_on_launch=${tmux_conf_update_plugins_on_launch:-true}
 #   tmux_conf_update_plugins_on_reload=${tmux_conf_update_plugins_on_reload:-true}
 #   tmux_conf_uninstall_plugins_on_reload=${tmux_conf_uninstall_plugins_on_reload:-true}
-#   tmux run -b "cut -c3- '$TMUX_CONF' | sh -s __apply_plugins '$window_active' '$tmux_conf_update_plugins_on_launch' '$tmux_conf_update_plugins_on_reload' '$tmux_conf_uninstall_plugins_on_reload'"
+#
+#   tpm_plugins=$(tmux show -gvq '@tpm_plugins' 2>/dev/null)
+#   if [ -n "$(tmux show -gv '@plugin' 2>/dev/null)" ] || [ -n "$tpm_plugins" ]; then
+#     if [ -z "$TMUX_PLUGIN_MANAGER_PATH" ]; then
+#       if [ "$(dirname "$TMUX_CONF")" = "$HOME" ]; then
+#         TMUX_PLUGIN_MANAGER_PATH="$HOME/.tmux/plugins"
+#       else
+#         TMUX_PLUGIN_MANAGER_PATH="$(dirname "$TMUX_CONF")/plugins"
+#       fi
+#       tmux set-environment -g TMUX_PLUGIN_MANAGER_PATH "$TMUX_PLUGIN_MANAGER_PATH"
+#     fi
+#     tmux run -b "cut -c3- '$TMUX_CONF' | sh -s __apply_plugins '$window_active' '$tmux_conf_update_plugins_on_launch' '$tmux_conf_update_plugins_on_reload' '$tmux_conf_uninstall_plugins_on_reload'"
+#   fi
 # }
 #
 # _apply_important() {