Make the Parser independent from the global C-locale

[vglavnyy]

This PR adds detection of locale-independent functions strdtod_l, strdtof_l, strdtoll_l, strdtoull_l instead of locale-wide strdtod, strdtoll, strdtoull .
After this PR the IDL parser will be fully compatible with the ASCII alphabet of the Flatbuffers grammar.

There are some direct calls of strdtod in the Flatbuffers code, these calls are not related to the parser directly (flexbuffer, reflection).

The parse has direct calls of local-wide atoi function.
A locale-safety of these calls requires investigation (however, all tests passed).

Minor changes:

1. Speed-up travis-ci builds using parallel compilation
2. Minor bug fixes in scalar_fuzzer.cc code

[aardappel]

Generally lookls good to me, thanks! Ready to go in?

[vglavnyy]

I think better replace the hard-coded FLATBUFFERS_TEST_LOCALE by an environment variable:

Enable test of locale independent code.
-DFLATBUFFERS_TEST_LOCALE="" - test with default C-locale
-DFLATBUFFERS_TEST_LOCALE="ru_RU.CP1251" - test with ru_RU.CP1251

to

1. std::getenv("FBS_TEST_LOCALE"); - in a code (since C++11)
2. FBS_TEST_LOCALE="ru_RU.CP1251" ./flattests - in a console
3. FBS_TEST_OPTIONS=LOCALE="ru_RU.CP1251" ./flattests - like ASAN/UBSAN

[aardappel]

Hmm, if you're sure this getenv works on all platforms, it is worth trying. Remember we support VS2010 (C++0x) and Android with STLPort. Rather than #ifdeffing those out, your current code may be more universal?

[vglavnyy]

Have done.
std::getenv passed all builds without #ifdef.

Additionally:

• some code have been formatted (test_assert.[cpp && h], util.h);
• the idl_parser.cpp file in the master branch has format UTF-8 with BOM while others files have UTF-8 without BOM. Current commit saved the file as simple UTF-8 without BOM;

Question:
Should the functions in util.h be inline: SaveFile, StripExtension, GetExtension, StripPath, StripFileName, ConCatPathFileName and etc?
Some #include directives may be removed from util.h if move these functions to util.cpp.

[vglavnyy]

VS2013-Release-x86 Rust failed with message memory allocation of 2147483648 bytes failederror: test failed, to rerun pass '--test integration_test'.

I have no idea why this error occurred.

[aardappel]

Thanks for the other fixes.
The Rust error is unrelated.
Yes, it be great to move some functionality in util.h to util.cpp to move #includes, in particular windows.h

[aardappel]

Merging this, util.h refactor can go in other PR.