mockftpserver: drop .classpath files and update README.txt am: 7a7323460c am: dfa2060ad0 am: ec64f179b5 am: dfae9b3ae7 am: ecccd08d3a am: 306569f045 am: 7b6075ff83 am: bcfe1c17c1 am: d7a7717a72 am: bf2a9288bc

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/mockftpserver/+/16495238

Change-Id: Id2236d9d934745af357739f561d48ab7c36e0cb4