add maxsplit fragment option (#5821)

* add maxsplit fragment option

* Add a docs folder

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Co-authored-by: 2dust <31833384+2dust@users.noreply.github.com>

V2rayNG/app/src/main/res/values/strings.xml

@@ -376,6 +376,7 @@
     <string name="title_pref_fragment_length">Fragment Length (min-max)</string>
     <string name="title_pref_fragment_interval">Fragment Interval (min-max)</string>
     <string name="title_pref_fragment_enabled">Enable Fragment</string>
+    <string name="title_pref_fragment_maxsplit">Fragment Max Split</string>
 
     <string name="update_check_for_update">Check for update</string>
     <string name="update_already_latest_version">Already on the latest version</string>