updated format to align with riscv-c template

changes since last pdf update listed below:
04/22/2021	updated adoc format to align with risc-v template, added revision history
04/18/2021	Added Bibliography section
04/15/2021	issue #45 - for rev1.0 mtvec not xtvec controls enabling CLIC mode for all priv
04/13/2021	issue #141 - N-extension vs Bare S-mode note added.
04/13/2021	issue #117,#125 fix - change text to match table in M/S/U system if nmbits==1
04/12/2021	issue #47 fix - add CLIC reset behavior section
04/12/2021	issue #26 fix - modify wording that defined micro-architectural behavior of xINHV
04/12/2021	issue #91 - add DTS entry example
04/12/2021	added CLIC comparision to Advance Interupt Architecture (AIA)
04/12/2021	issue #111,#105 fix - For hardware vectoring access exceptions, both {tval} and {epc} holds the faulting address
04/08/2021	issue #49, #79 - downplay M/S/U memory map requirements
03/30/2021	issue #29 - updated memory map table reserved section to give room for clicinttrig
03/30/2021	issue #122 fix - remove wording referring to register