Allow suiteSetUp() and suiteTearDown() to be provided as normal C functions (Thanks @jlindgren90 )

Fix missing TEST_ASSERT_EACH_EQUAL_HEX_MESSAGE -- Thanks @codehearts !

Color test results using ANSI escape codes (Thanks for the work, @VLambret !)

Help error detection by adding specific colors for test results. This
behavior is activated only when unity if compiled with UNITY_COLOR flag.

Bugfix greater/less than asserts with unsigned int. (Thanks @jsalling! I can't express what a GREAT job you did with this.)

- Enable support for Green Hills Software compiler
- Define weak implementations only once except on Windows

MinGW supports a limited form of weak symbols, with the restriction
that weak/default implementations need to be defined in the same
translation unit they are called from.  Strong/overriding symbols
may of course be specified in a different translation unit.

 Make all comparison operators on integers available

 Check for unsigned types, add 'or equal to' support
 Consolidate to one function to remove repeated code

This is simpler and more flexible than embedding C code in the Ruby options
(:suite_setup and :suite_teardown).  However, support for :suite_setup and
:suite_teardown is kept for backwards compatibility.

Several configurations are possible:
1. :suite_setup and :suite_teardown options provided and used.
2. :suite_setup and :suite_teardown options not provided (nil):
  2a. Weak symbols not supported; suiteSetUp() and suiteTearDown() are not called.
      It would be simpler to make user-provided functions mandatory in this case,
      but it could break some pre-existing test suites.
  2b. Weak symbols are supported and the stub implementations of suiteSetUp() and
      suiteTearDown() are called if there are no user-provided functions.
  2c. Weak symbols are supported but overridden by user-provided suiteSetUp() and
      suiteTearDown() functions.

Fix compiler warning due to reusing symbol 'exp'.

Cleanup Greater than and Less than asserts from other PR (#264) (Thanks @dpostorivo and @Dommar92 !)

Rewrite UnityPrintFloat to match printf("%.6g").

The existing implementation was not very good:
 - It printed all very small values as "0.000000..."
 - It did not distinguish positive and negative zero
 - In some cases it printed extra garbage digits for single-precision values
   (e.g. 3.9e+30 was printed as 3.90000013+30)

Tests have been updated to check that we now match printf("%.6g") for
1,000,000 randomly chosen values, except for rounding of the 6th digit.

Allow specifying custom header declaration (Thanks!)

The user can specify UNITY_OUTPUT_CHAR_HEADER_DECLARATION and
UNITY_OUTPUT_FLUSH_HEADER_DECLARATION when he would like to declare
UNITY_OUTPUT_CHAT or UNITY_OUTPUT_FLUSH respectivly

- Fixed some style issues.

Fixed UNITY_TEST_ASSERT_EACH_EQUAL_*

Fixed copy-paste error for:
- UNITY_TEST_ASSERT_EACH_EQUAL_INT64
- UNITY_TEST_ASSERT_EACH_EQUAL_UINT64
- UNITY_TEST_ASSERT_EACH_EQUAL_HEX64

So that the comparison is done on the expected _value_ instead of the _array_.