Csr schema update (#17)

* Misa skeleton done.

* Done mtvec,mideleg,medeleg,id csrs,mstatus.

* fixed alignment and trailing whitespaces

* Machine csrs almost done.

* changing exists to implemented

* removing reset-values from sub-fields

* Added defaults and minimized required fields in yaml.

* adding isa specific checks

* adding max length check for reset-values

* adding misa to default setter

* misa checks done.

* missed adding updated schema for misa-checks

* Trimming function done.

* Fixed bug in trimming function.

* few checks for readonly machine csrs.

* example to show trimming doesn't work

* Fixed trimming function.

* RO reset value check added.

* fixed misa reset-val check when misa is not defined by user.

* defined types for mtvec fields

* specific check for mtvec

* removing trailing spaces

* adding reset value checks for mtvec

* Create csr_template_draft1.yaml

* adding support for delegation registers

* rv32i

* Changes done

* Changes done

* changes done

* Seperate warl class added

* Update modes done

* support for bitmask done

* support for bitmask done

* changes done

* Changes done

* Changes done

* Changes done

* changes done

* Changes done

* Changes finalized

* Minor bug fixes for erratic check functions.

* Function for reset value checking done.

* Example update.

* updated docs

* adding platform yaml docs

* updated schemavalidator for ISA checks

Close #10
Close #11
Close #12
Close #13

* renaming mcause

* adding changelog and removed obsolete files

* Added counter registers.

* Removed redundant functions and obsolete code.

* Example update.

* Formatting for wpri fields.

* Yapf formatting for files.

* Dependency fix.

Co-authored-by: dracarys99 <spawan1999@gmail.com>
Co-authored-by: lavanyajagan <lavanya.jagan@gmail.com>
Co-authored-by: Sujeet <sujeettogo@gmail.com>