Add Buffer class to store data and track its size

Buffer has a char array and a counter that is incremented every time
data is appened to the buffer.
Merge branch 'master' into buffer
Add buffer append methods for commonly used struct types
Rename Buffer to NetworkBuffer

To indicate that the contents are stored in network byte order.
Add unit tests for NetworkBuffer
Fix append integer methods
Add return to all NetworkBuffer append methods

append now returns the number of items added to the buffer; 0 is returned if there is not
enough space in the buffer to append.
Expand buffer unit tests.

Check return value of append calls and add a test to append multiple types of data.
Format buffer code

I forgot public functions are going to be Capitalized.
Merge pull request #14 from tcoyne/buffer

Add Buffer class to store data and track its size