cdiff: Replace cdiff-apply feature with Rust implementation

Apply both .cdiff and .script CVD patches.

Note: A script is a non-compressed and unsigned file containing cdiff
commands. There is no header or footer that should be processed.

This Rust-based implementation of the cdiff-apply feature includes
equivalent features as found in the C-based implementation:
- cdiff file signature validation against sha256 of the file contents
- Gz decoding of file contents
- File open command
- File close command
- Signature add command
- Line delete command
- Xchg command
- Move command
- Unlink command

This Rust implementation adds cdiff-apply unit tests to verify correct
functionality.

Cargo.toml

@@ -3,3 +3,6 @@
 members = [
     "libclamav_rust",
 ]
+
+[profile.dev.package."*"]
+opt-level = 2

common/CMakeLists.txt

@@ -15,7 +15,6 @@ add_library( common STATIC )
 target_sources( common
     PRIVATE
         cert_util.c
-        cdiff.c
         actions.c
         clamdcom.c
         getopt.c
@@ -27,7 +26,6 @@ target_sources( common
         tar.c
     PUBLIC
         cert_util.h
-        cdiff.h
         actions.h
         clamdcom.h
         fdpassing.h