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

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

Change-Id: I9c4f0300e082c99b6490e01165f5a31c3e624709