Remove sha1 and base64 functions

Having sha1 requires dependency on OpenSSL when it is not necessary. A filesystem library should ONLY provide the basic functionality to traverse folders, and provide means to read/write to file streams. Nothing more.

Hash/base64 etc. can, and should, be provided outside the library.

Start by searching the repository for the sha1 and base64 functions and their OpenSSL dependency. Trace their declarations, implementations, and callers before removing the filesystem library's hash and encoding functionality. Done means those functions and the unnecessary dependency are gone without leaving references.

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