Remove README.md from repository

The README.md file will be a standalone file like wiki page from now on.
Change version number to 0.11.1
Change versionCode to 5
Change version number to 0.11.1 in LICENSES file
Change version number to 0.11.1 in about activity
Release 0.11.1

Remove README.md file from repository.

* hotfix-0.11.1:
  Change version number to 0.11.1 in about activity
  Change version number to 0.11.1 in LICENSES file
  Change versionCode to 5
  Change version number to 0.11.1
  Remove README.md from repository