refactor applypatch and friends

Change the applypatch function to take meaningful arguments instead of
argc and argv.  Move all the parsing of arguments into main.c (for the
standalone binary) and into install.c (for the updater function).
applypatch() takes patches as Value objects, so we can pass in blobs
extracted from the package without ever writing them to temp files.

The patching code is changed to read the patch from memory instead of
a file.

A bunch of compiler warnings (mostly about signed vs unsigned types)
are fixed.

Support for the IMGDIFF1 format is dropped.  (We've been generating
IMGDIFF2 packages for some time now.)

Change-Id: I217563c500012750f27110db821928a06211323f
diff --git a/applypatch/utils.h b/applypatch/utils.h
index d6d6f1d..bc97f17 100644
--- a/applypatch/utils.h
+++ b/applypatch/utils.h
@@ -23,8 +23,8 @@
 void Write4(int value, FILE* f);
 void Write8(long long value, FILE* f);
-int Read2(unsigned char* p);
-int Read4(unsigned char* p);
-long long Read8(unsigned char* p);
+int Read2(void* p);
+int Read4(void* p);
+long long Read8(void* p);