Improved windows stack traces

Made windows stack trace much more resilient (#552)

* SymSetOptions, try to be more resilient

* Write symbol name and addr if file/line cannot be found

* Simplified and cleaned up symbol printing, ensure that we get the most info possible

* fflush at the end of aws_backtrace_print()

* fflush and free, clang-format

Fix for ancient linux

v0.4.20

Fix for old linux (#545)

Stack dump improvements

v0.4.19

Added newlines to stacktrace headers (#541)

Stack dump improvements

v0.4.18

Always print both raw and resolved stack trace, helps in release buil…

Memory tracing updates

v0.4.17

Fixed probing for stack trace availability (#537)

Memory Tracing

Generalized Mem tracing (#536)

* Ported alloc tracer from Java CRT, added unit tests

* Generalized backtrace/backtrace_symbols for multiple platforms

* Added tests to ensure midstream usage works

* Stack trace decoding test now uses virtual logger

* Fixed AWS_VARIABLE_LENGTH_ARRAY on windows, causing stack corruption

* Converted all tests to use the mem tracer

* Removed allocator from test harness structure, enabled logging by default

aws_string_c_str() helper fn

v0.4.15

aws_string_c_str() (#534)

Fix alignment on Windows

v0.4.14

Remove AWS_ALIGN, as it doesn't work reliably, add AWS_ALIGNED_TYPEDE…

Added ring_buffer allocator, AWS_UNREACHABLE

Imported ring buffer allocator from node CRT (#527)

* Imported ring buffer allocator from node, fixed bugs, added unit test

* Implemented realloc as an assert to prevent use

Fixed visibility on static libs, added secure string length functions, fixed buffer overflow vulnerability in stack trace printing.

v0.4.12

Don't set fvisibility on static libs. (#516)