Cleanup error handling and replace RC_TYPE enum with defines. POSIX 0 is OK

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
Massive cleanup, change ALL_CAPS_TYPES to lower_caps_t type, etc.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
Fix issue #33: Reindent all code to use Linux kernel style

Please note, the code derived from Polar SSL should use its
own coding style, for easier diff/patch merge from upstream.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>