* zig build system: create standard dynamic library sym links
* unwrapping an error results in a panic message that contains
the error name
* rename error.SysResources to error.SystemResources
* add std.os.symLink
* add std.os.deleteFile
* See #204 - zig build system
* allow builtin types Os, Environ, Arch to be used at runtime.
they have zero_bits=false and debug info now.
* Eradicate use of `@alloca` in std for syscalls. See #225
* add `std.io.writeFile`
* `std.debug.panic` adds a newline to format
* In-progress os.ChildProcess.spawn implementation. See #204
* Add explicit cast from integer to error. Closes#294
* fix casting from error to integer
* fix compiler crash when initializing variable to undefined
with no type