Default signedness is unsigned not signed.

see http://www.erlang.org/doc/programming_examples/bit_syntax.html#Defaults
Merge pull request #9 from matthias-endler/fixes_ch3

Default signedness is unsigned not signed.
Merge remote-tracking branch 'upstream/master'
Merge pull request #10 from nuked/master

Various updates for typesetting.
Merge remote-tracking branch 'upstream/master'
Small typesetting changes for chapter 7.