[debug-toolbar] make linter happy

[pyramid/ctl/debugtoolbar] automatically include custom panels on -t

[debug-toolbar/rql] display sql queries generated by rql ones

[debug-toolbar/rql] add RQL panel Closes #17219673

[debug/emit/rql] add RQL debug channel and emit queries This is used for the RQL debug panel but can be used as a generic mechanism for several tools.

[debug/source_highlight] rename highlight to highlight_terminal

[debug/source_highlight] add highlight_html and generate_css for debugtool panels

[debug/rql] bind a uniq token per rql to trace its decomposition This is aimed to be used by the RQL debug panel (and the SQL one later on) but can also be used by other debugging tools.

[debug] add a new channel events mechanism for debugging

[ctl] allow to specific instance name for instance commands in $CW_INSTANCE Closes #17253994

[cubicweb/utils] add QueryCache.__contains__() to improve dict-like behavior. Closes #255426

[migrations/pdb] add to every failing migration operation a "p(db)" option Instead, the migration command will just crash without offering the possibility of the user to debug or continue the migration. Closes #17219772

[pyramid/ctl] add a new option to activate the debugtoolbar (-t) While this toolbar isn't yet very integrated with CW, it integrates an inline debugging shell like werkzeug for flask or django_extensions which greatly helps debugging on exception. It can already be manually activated by writting "pyramid.includes = pyramid_debugtoolbar" but it's hidden somewhere in the documentation and not very accessible and annoying to do. Closes #17219765

[changelog] add missing information to the 3.27 changelog

Merge 3.26

[debug] add ALL possibility to --dbglevel

[ux] display instance name in suggested upgrade command

[migration/pdb] display traceback instead of only the exception for easier debugging Closes #17219820

[migration/pdb] add option to use pdb.post_mortem if traceback is provided Post mortem is a mode where the pdb shell is opened **where** the exception as occured instead at the breakpoint for set_trace. This is way more useful for debugging for the user because is will have the full context of the error. Closes #17219827

[migration/shell] select ipdb if present on (d)ebug mode Closes #17219833

[mod] move get_pdb to utils.py

Add a migration function in order to relocate bfss Related to https://www.cubicweb.org/ticket/1903304

[pyramid/debug] on every request display request path and selected controller This will display lines like: 2019-06-12 16:26:57 - (cubicweb.pyramid.bwcompat) INFO: REQUEST [view] '/wiki/334037' selected controller <cubicweb.web.views.basecontrollers.ViewController object at 0x7f133802ae90> at /root/.virtualenvs/abreton/local/lib/python2.7/site-packages/cubicweb/web/views/basecontrollers.py:120 2019-06-12 16:26:59 - (cubicweb.pyramid.bwcompat) INFO: REQUEST [data] '/data/ea5eb3b6f89fba0ff4b671093c88d3dd/images/cartouche-mur.jpg' selected controller <cubicweb.web.views.staticcontrollers.DataController object at 0x7f1332a84d50> at /root/.virtualenvs/abreton/local/lib/python2.7/site-packages/cubicweb/web/views/staticcontrollers.py:179 The make debugging easier as this isn't done already. Most other web frameworks do something similar for the developper to be able to understand what is happening right now. Closes #17219741

[logging/debug] move transaction operations logs from self.debug to DBG_OPS There were a mixing between displaying transaction operations log on logger.debug and only when DBG_OPS was on, uniformize everything behind DBG_OPS. Closes #17229126