First optimzation with a new dynamic way to compute the refresh rate. Good news, the CPU consumption seams to be lower than ~20% with a refresh rate more or less the same...

Some field name are incorrect in CSV export #1372 and Prohibit some plug-in data from being exported to influxdb #1368

This reverts commit efaadb4b.

Remove 'glances_' prefix from filenames.

__init__ method from base class 'GlancesStats' is not called.

Already added with commit https://github.com/nicolargo/glances/commit/6bef4843be1c2e3c33441d5395524ceb192dd950.
Restore and update it with export modules support.

- import statements are in the wrong order.
- missing whitespace around arithmetic operator
- blind except: statement
- multiple imports on one line
- trailing whitespace
- blank line contains whitespace
- line break before binary operator
- missing whitespace after ','
- block comment should start with '# '
- multiple spaces before operator
- 'logger' imported but unused
- expected 2 blank lines, found 1