[2982] First draft of Hooks user guide
[3015] Integer Element test is changed to uint64_t
[2771] convert HTML-style tables to docbook

NOTE: that my renderer, dblatex, is putting the huge table on one page.
I need to solve that.
[3015] Type of IntElement is changed from long int to int64_t.
       Element::create accepts char, short, int, long, long long, int32_t and int64_t.
       IntElement->intValue() returns int64_t.
       IntElement->getValue() and IntElement->setValue() accept int64_t only.
[2856] Extend SegmentInfo and add some basic tests

This is according to the description in #2856, but it needs further
testing and also documentation. These will be added in future commits
after handling "load" command in the MemorySegmentBuilder.
[2856] Move command handlers into their own methods
[2856] Pass tuples in the command queue
[2856] Add "load" command handler
[3015] Rewrote to use boost::lexical cast to convert string to values
[3016] added 64bit counter test (it takes 10 seconds)
[3016] Counter::Value is changed to uint64_t and auth outputs 63bit of values
[2856] Add state transition test helpers, and extend complete_update() tests
[2856] Test UPDATING -> SYNCHRONIZING with and without events in the queue
[2856] Move test in file
[2856] Fix test name
[2856] Add add_reader() tests
[2856] Reorder methods
[2856] Fix exception messages
[2856] Check that old_readers is untouched by add_reader()
[2856] Add start_update() tests