Builds on mac.

[thesamprice]

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System(s) tested on

• Hardware: [e.g. PC, SP0, MCP750]
• OS: [Mac OSX]
• Versions: [e.g. cFE 6.6, OSAL 4.2, PSP 1.3 for mcp750, any related apps or tools]

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[thesamprice]

Not sure if this is wanted or not.

This was pulled from
https://gist.github.com/yinyin/2027912

im trying to port cfs to mac via a qt osal layer.

[skliper]

Related to #95. Suggestion is to remove endian.h dependency all together in favor of a custom/portable set of conversion functions.