Replace all crypto libraries with Botan

Selected the [Botan crypto library](https://github.com/randombit/botan) due to its feature list, maintainer support, availability across all deployment platforms, and ease of use. Also evaluated Crypto++ as a viable candidate, but the additional features of Botan (PKCS#11, TPM, etc) won out.

The random number generator received a backend upgrade. Botan prefers hardware-based RNG's and will provide one if available. This is transparent to KeePassXC and a significant improvement over gcrypt.

Replaced Argon2 library with built-in Botan implementation that supports i, d, and id. This requires Botan 2.11.0 or higher. Also simplified the parameter test across KDF's.

Aligned SymmetricCipher parameters with available modes. All encrypt and decrypt operations are done in-place instead of returning new objects. This allows use of secure vectors in the future with no additional overhead.

Took this opportunity to decouple KeeShare from SSH Agent. Removed leftover code from OpenSSHKey and consolidated the SSH Agent code into the same directory. Removed bcrypt and blowfish inserts since they are provided by Botan.

Additionally simplified KeeShare settings interface by removing raw certificate byte data from the user interface. KeeShare will be further refactored in a future PR.

NOTE: This PR breaks backwards compatibility with KeeShare certificates due to different RSA key storage with Botan. As a result, new "own" certificates will need to be generated and trust re-established.

Removed YKChallengeResponseKeyCLI in favor of just using the original implementation with signal/slots.

Removed TestRandom stub since it was just faking random numbers and not actually using the backend. TestRandomGenerator now uses the actual RNG.

Greatly simplified Secret Service plugin's use of crypto functions with Botan.

CMakeLists.txt

@@ -86,12 +86,6 @@ if(WITH_XC_ALL)
     endif()
 endif()
 
-if(WITH_XC_SSHAGENT OR WITH_XC_KEESHARE)
-  set(WITH_XC_CRYPTO_SSH ON)
-else()
-  set(WITH_XC_CRYPTO_SSH OFF)
-endif()
-
 # Prefer WITH_XC_NETWORKING setting over WITH_XC_UPDATECHECK
 if(NOT WITH_XC_NETWORKING AND WITH_XC_UPDATECHECK)
     message(STATUS "Disabling WITH_XC_UPDATECHECK because WITH_XC_NETWORKING is disabled")
@@ -250,6 +244,7 @@ if(WITH_APP_BUNDLE)
 endif()
 
 add_gcc_compiler_flags("-fno-common")
+check_add_gcc_compiler_flag("-fopenmp")
 add_gcc_compiler_flags("-Wall -Wextra -Wundef -Wpointer-arith -Wno-long-long")
 add_gcc_compiler_flags("-Wformat=2 -Wmissing-format-attribute")
 add_gcc_compiler_flags("-fvisibility=hidden")
@@ -269,7 +264,6 @@ else()
 endif()
 endif()
 
-add_gcc_compiler_cxxflags("-fno-exceptions -fno-rtti")
 add_gcc_compiler_cxxflags("-Wnon-virtual-dtor -Wold-style-cast -Woverloaded-virtual")
 add_gcc_compiler_cflags("-Wchar-subscripts -Wwrite-strings")
 
@@ -324,7 +318,7 @@ if(APPLE AND CMAKE_COMPILER_IS_CLANGXX)
 endif()
 
 if(WITH_DEV_BUILD)
-    add_definitions(-DQT_DEPRECATED_WARNINGS -DGCRYPT_NO_DEPRECATED)
+    add_definitions(-DQT_DEPRECATED_WARNINGS)
 else()
     add_definitions(-DQT_NO_DEPRECATED_WARNINGS)
     add_gcc_compiler_cxxflags("-Wno-deprecated-declarations")
@@ -447,20 +441,22 @@ endif()
 # Make sure we don't enable asserts there.
 set_property(DIRECTORY APPEND PROPERTY COMPILE_DEFINITIONS_NONE QT_NO_DEBUG)
 
-find_package(LibGPGError REQUIRED)
-find_package(Gcrypt 1.7.0 REQUIRED)
-find_package(Argon2 REQUIRED)
+# Find Botan2
+find_package(Botan2 REQUIRED)
+if(BOTAN2_VERSION VERSION_LESS "2.11.0")
+    message(FATAL_ERROR "Botan2 2.11.0 or higher is required")
+endif()
+include_directories(SYSTEM ${BOTAN2_INCLUDE_DIR})
+
+# Find zlib
 find_package(ZLIB REQUIRED)
-find_package(QREncode REQUIRED)
-find_package(sodium 1.0.12 REQUIRED)
-
-set(CMAKE_REQUIRED_INCLUDES ${ZLIB_INCLUDE_DIR})
-
 if(ZLIB_VERSION_STRING VERSION_LESS "1.2.0")
     message(FATAL_ERROR "zlib 1.2.0 or higher is required to use the gzip format")
 endif()
+include_directories(SYSTEM ${ZLIB_INCLUDE_DIR})
 
-include_directories(SYSTEM ${ARGON2_INCLUDE_DIR} ${sodium_INCLUDE_DIR})
+# QREncode required for TOTP
+find_package(QREncode REQUIRED)
 
 # Optional
 if(WITH_XC_YUBIKEY)
@@ -499,7 +495,7 @@ if(UNIX)
     endif()
 endif()
 
-include_directories(SYSTEM ${GCRYPT_INCLUDE_DIR} ${ZLIB_INCLUDE_DIR})
+include_directories(SYSTEM ${ZLIB_INCLUDE_DIR})
 
 add_subdirectory(src)
 add_subdirectory(share)