Add note about Issue 7648 to `std.stdio.File`.

Issue URL: http://d.puremagic.com/issues/show_bug.cgi?id=7648
Fix issue in `std.json` when `null` is returned instead of empty string/array.
fix Issue 9431 - Tuple creation problem with array of array
Fix big endian version of MD5 and RipeMD160.

Obviously the code has never been run on a big endian architecuture.
With these changes the unit tests passes on Linux/PPC64.
add an overload for uniform!enum that takes a generator
Fix big endian issue in std.internal.math.biguintcore.d

The unit tests passes with this change on Linux/PPC64.
Fix endian issues in std.md5

I replaced the methods Encode and Decode with calls to methods
from std.bitmanip. This solves the endian issues.
DDoc -std.stdio: exceptions thrown by C-like API.

Updated documentation for all the C-like member functions \
(and the File ctor) to specify exactly what gets thrown when. 

(note: Exceptions in std.stdio are a mess and should be made 
 more consistent. Also, it seems some member functions that 
 should check if the file is opened do not, but I don't know
 if that might be intentional (as the C functions should fail 
 anyway, resulting in a throw))
Fix endian issue in std.bitmanip

BitArray uses an array of size_t elements but opEquals() and opCmp()
cast it to an array of ubyte elements. On a big endian architecture
the bytes are accessed in wrong order.
The solution is to always use size_t elements.
Merge pull request #1254 from redstar/endianbitmanip

Fix endian issue in std.bitmanip
Merge pull request #1249 from redstar/digestendian

Fix big endian version of MD5 and RipeMD160.
Merge pull request #1250 from redstar/bigintendian

Fix big endian issue in std.internal.math.biguintcore.d
Cleanup digest source.

Removes an unnecessary cast and variable initialization.
Merge pull request #1247 from NilsBossung/uniform_enum

fix Issue 9888 - std.random.uniform!enum(generator) fails
Fix endian-dependent unit test.

The input to the digest tests is not endian-neutral. This is now
considered. The big endian values were derived by writing the data
into a file and running md5sum and sha1sum with the file as input.
Merge pull request #1257 from redstar/digestunittest

Fix endian-dependent unit test.
Merge pull request #1256 from redstar/digestcleanup

Cleanup digest source.
Merge pull request #1243 from 9rnsr/fix9431

Issue 9431 - Tuple creation problem with array of array
Use atomicOp instead of InterlockedIncrement to fix Win64 linker errors.
Merge pull request #1253 from s-ludwig/master

Win64 linking fix for std.c.windows.com