EELSSpectrum.estimate_FWHM now works for multidimensional signals
Rename estimate_FWHM to estimate_peak_width and polish it
Move estimate_peak_width to Signal1DTools and add tests
Add documentation to DictionaryBrowser and make it iterable. Rename
its len method to __len__ and modify the keys method so that it
does not returns private keys, nor they are now counted by len.
BUG-FIX: 2 bugs fixed:\n* DictionaryBrowser was raising an exception when iterating an empty dictionary.\n* DictionaryBrowser was polluting the dictionary returned by the as_dictionary method with the interator index.
Add DictionaryBrowser.add_dictionary method
Add support for dm4 files, fixes #8 and fixes #30. The digital micrograph
reader has been almost fully rewritten and it should now be able to read
a higher number of dm3 files.
Add DictionaryBrowser.get_item
Merge branch 'ENH_DictionaryBrowser' into ENH_dm4
Remove dm3reader.py that we no longer use
Better emi xml reader and fix a bug that raised an exception when loading image stacks
Merge branch 'ENH_dm4' into ENH_FEI_reader

Conflicts:
	hyperspy/tests/signal/test_1D_tools.py
Small corrections to the docs
Merge branch 'master' into ENH_dm4

Conflicts:
	hyperspy/tests/signal/test_1D_tools.py
Add mapping to some parameters
Let the dm reader guess the axis names.
Add verbose argument to dm reader
Remove unused DictBroswer
Remove unused read_data_array
DM reader: Reorder the RGBA fields