chore(windows): remove DCPCrypt

Looks like we use dcpcrypt now only for two reasons:

1. Encrypting user's proxy server settings. This should not be needed (Proxy dialog should be removed, we should always read from system settings).
2. Generating MD5 hashes. Used only by project files in Developer (as we move towards a folder model in Developer, this will no longer be needed either). Alternative MD5 units are available, for example Indy has an MD5 unit. Also, system.Hash.