This changes removes classes of the obsolete logging frame work and
all its references. It was not used anywhere, but included in several
headers.
Had to add header QDateTime in some places, which was not correctly
included and now missing.
refs #90
* rename CStatusMessages to CStatusMessageList
* rename NetworkVatlib to CNetworkVatlib
* replace all occurrences of Realname with RealName (correct camel case)
* CSequence method corresponding to CList::append is push_back
* don't compile the qdbuscpp2xml metadata plugin by default
* CAircraftIcao string members always trimmed and capitalized
* added CComSystem::roundTo25KHz
* using epsilon comparison in a couple of places
refs #81
Some interesting results:
* Minor simplification of PQ converters and unit ctors; may not seem like much, but I think it enables possible future simplifications of a similar kind.
* CMeasurementPrefix is gone, no longer needed. Now prefixes are applied at the template stage.
* Apart from that, PQs public API is unchanged.
* Discovered that ft/s^2 conversion factor was wrong: fixed.
* Default unit is more clearly stated in one place, not restated in many different places, and is not always the SI unit
* Converter strategy pattern in CMeasurementUnit, covering linear, affine, and different kinds of sexagesimal units
* General reorganization of CMeasurementUnit construction and CPhysicalQuantity methods, not removing any behvaiour
* Move duplicated method unitFromSymbol from derived classes into base class CMeasurementUnit
* For DBus, CPhysicalQuantity marshals both in its own unit and in the default unit
