Python Linting and Code Formatting (#298)

* Create common print_diff function

* Add pylint and black

* Fix linting, move classes to utils

* Add black/pylint to github actions

* Fix linting

* Move Bin and SymInfo into their own files

* Split out format

* Tidy up workdlows and pip, add readme

* Lint tests, add tests to readme

tools/isledecomp/isledecomp/bin.py

@@ -0,0 +1,47 @@
+import struct
+
+
+# Declare a class that can automatically convert virtual executable addresses
+# to file addresses
+class Bin:
+    def __init__(self, filename, logger):
+        self.logger = logger
+        self.logger.debug('Parsing headers of "%s"... ', filename)
+        self.filename = filename
+        self.file = None
+        self.imagebase = None
+        self.textvirt = None
+        self.textraw = None
+
+    def __enter__(self):
+        self.logger.debug(f"Bin {self.filename} Enter")
+        self.file = open(self.filename, "rb")
+
+        # HACK: Strictly, we should be parsing the header, but we know where
+        #      everything is in these two files so we just jump straight there
+
+        # Read ImageBase
+        self.file.seek(0xB4)
+        (self.imagebase,) = struct.unpack("<i", self.file.read(4))
+
+        # Read .text VirtualAddress
+        self.file.seek(0x184)
+        (self.textvirt,) = struct.unpack("<i", self.file.read(4))
+
+        # Read .text PointerToRawData
+        self.file.seek(0x18C)
+        (self.textraw,) = struct.unpack("<i", self.file.read(4))
+        self.logger.debug("... Parsing finished")
+        return self
+
+    def __exit__(self, exc_type, exc_value, exc_traceback):
+        self.logger.debug(f"Bin {self.filename} Exit")
+        if self.file:
+            self.file.close()
+
+    def get_addr(self, virt):
+        return virt - self.imagebase - self.textvirt + self.textraw
+
+    def read(self, offset, size):
+        self.file.seek(self.get_addr(offset))
+        return self.file.read(size)