Convert PDF docs to markdown (Thanks for all the work, @wolf99 !)

Add newlines after headings for best practice, trim trailing spaces & convert sneaky incorrectly coded chars

blank newline after headins is apparently best practice according to http://stackoverflow.com/q/42953462/1292918

Add GFM version of getting started guide PDF

Add GFM version of configuration guide PDF

Add GFM version of helper scripts guide PDF

Add GFM version of coding standard PDF

Add GFM version of assertions reference PDF

Change markdown used to italicise line. Switched to use asterisk markdown instead

Started to flesh out rubocop settings for this project. Added rakefile tasks to do so. Updated first script to make it compliant.

Starting to enforce our coding style. The first step is that we’ve pulled in Rubocop to check out Ruby syntax. There is likely a bit of customization to do yet AND there is definitely that backlog of todo’s that we just told it to ignore.

Fix -Wconversion with gcc-4.3

Turn UNITY_OUTPUT_FLUSH off by default. Added a quick-define for the most common case: UNITY_USE_FLUSH_STDOUT. Clarified documentation. Fixes issue #269

Fix gcc warning with ubsan and -Wconversion

This fixes a compiler warning about a lossy conversion from long
unsigned int to int when compiling unity with gcc 6.3.1 and
the options -std=c89 -Wconversion -fsanitize=undefined

Fix warnings with -Wdouble-promotion

This fixes compiler warnings that clang produces with the
-Wdouble-promotion compiler option.

This only happens if double precision floating point numbers are
enabled.

The implicit double promotion occurs because numbers of type UNITY_FLOAT
are passed into UnityPrintFloat, which expects const UNITY_DOUBLE.

This commit fixes it by explicitly casting to UNITY_DOUBLE.

Fixed incorrect TEST_PROTECT explanation in readme