file interrupt.rs: based on https://github.com/rust-embedded/cortex-m

Copyright (c) 2016 Jorge Aparicio

licensed under the MIT or under the Apache-2.0 license

===============================================================================

https://github.com/chipKIT32/pic32-part-support
file crt0.S: modified for usage with Rust (C-related parts removed)
file general-exception.S
file cp0defs.h
file regdef.h
linker script(s) may contain fragments from pic32-part-support

Copyright (c) 2014, Microchip Technology Inc. and its subsidiaries ("Microchip")
All rights reserved.

This software is developed by Microchip Technology Inc. and its
subsidiaries ("Microchip").

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derived from this software without specific prior written permission.

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===============================================================================