Resolve "Wago - Tango device server bug on get(... flat=False)"

Closes #1369

See merge request bliss/bliss!2061

new style comm

See merge request bliss/bliss!2156

pancino authored Feb 13, 2020 and Piergiorgio Pancino committed Feb 28, 2020

 - exception on __info__ after wago refactor
 - improved __info__ in case of logical_devices with the same name that
   belows to different physical modules

 - fixed behaviour of get(.. ,flat=False)
 - Added missing kwargs (flat, cached)
Wago
 - checked data form for `get` and added test

Id19 fixes

See merge request !2068

tango_display_unit can also be "None"

See merge request !2148

Replace anyway the previous plot model if there was none

Closes #1419

See merge request !2153

Merge branch '1414-data-policy-documentation-update-various-doc-improvements-new-instrument-key-in-config' into 'master'

Resolve "Data policy documentation update, various doc improvements, new "instrument" key in config"

Closes #1414

See merge request !2142

- split installation in two sections: one for ESRF, one outside ESRF
- move ESRF data policy servers setup to ESRF installation chapter

[flint] Clean up small things

See merge request !2147

[writer] handle name collisions in the measurement group

See merge request !2152

[writer] add mythen to name mapping

See merge request !2151

[flint] Fix memory leak relative to Qt object unreleased

See merge request !2150