Add changes to README and CHANGELOG

CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Development
 
+* Release GIL during the computation of the CRC32C hash.
+* Added new parameter `gil_release_mode` for either keeping the GIL as long as given data is less than 32KiB or always releasing or keeping it  
+* Allow `kwargs` in general (buffer is given with `data`, initial CRC value with `value` and GIL release mode with `gil_release_mode`)
 * Adding explicit fallthrough annotations
   in several ``switch`` C statements
   for clarity, and to avoid potential warnings (#46).

README.rst

@@ -29,9 +29,9 @@ by older compiler versions.
 Usage
 -----
 
-The only method exposed by this module is ``crc32c(data, [crc])``.
+The only method exposed by this module is ``crc32c(data, [value])``.
 It computes the CRC32C checksum of ``data``
-starting with an initial ``crc`` checksum,
+starting with an initial ``value`` checksum,
 similarly to how the built-in ``binascii.crc32`` works.
 It can thus be used like this:
 
@@ -40,14 +40,23 @@ It can thus be used like this:
   print(crc32c.crc32c(b'hello world'))
   # 3381945770
   crc = crc32c.crc32c(b'hello')
-  print(crc32c.crc32c(b' world', crc))
+  print(crc32c.crc32c(b' world', value=crc))
   # 3381945770
 
 In older versions,
 the function exposed by this module was called ``crc32``.
 That name is still present but deprecated,
 and will be removed in new versions of the library.
 
+There is another keyword argument called ``gil_release_mode``
+which specifies whether a call of this library shall release
+or keep the GIL (https://wiki.python.org/moin/GlobalInterpreterLock).
+It can be set to these values:
+
+* -1 (or less): Automatic mode, i.e. keep the GIL as long as given data buffer is less than 32KiB
+* 0: Always keep the GIL
+* 1: Always release the GIL
+
 Additionally one can consult
 the following module-level values: