SectionHDF5: child section have now a parent

There was a bug in SectionHDF5::getSection where the parent section was not set for the returned child. This commit fixes this problem.
Merge pull request #260 from stoewer/master

> SectionHDF5: child section have now a parent
nice!
File and FileHDF5 now have the method location

```File``` and ```FileHDF5``` now have the method ```location``` to get a uri (```string```) for the ```File``` entity. In the case of the HDF5 backend this uri is the file name returned by ```H5File::getFileName()```.
Implemented tests as well.
Modified camelCase params & _underscore params

Adressing issue #255 all function parameters have changed from ```camelCase``` to ```camel_case``` and from ```_underscore``` to ```underscore```.
Merge pull request #261 from balint42/file_location

File and FileHDF5 now have the method location

Thanks!
Merge pull request #262 from balint42/camelcase_underscore

Cool!
Modified dimension producing factories to return specific dim types

All ```create*Dimension``` and ```append*Dimension``` factories now return their specific type denoted as ```*``` and thus it is now possible to write
```
RangeDimension dim = data_array.appendRangeDimension(ticks);
```
while it still remains possible to do
```
Dimension dim = data_array.appendRangeDimension(ticks);
```
Merge pull request #263 from balint42/dimension_types

Modified dimension producing factories to return specific dim types

OK