Storage: drop index on PATH

length problem with mysql, not enough entries to worry about for now
autogenerate names for snippets' MIMEtypes
ignore mysql's "varchar-to-text conversion" warning
Move warning setup to pybble.__init__
Use a bunch of constants for data lenghts
Ignore spurious warning in script test
Alembic stamping after setup
more database doc stuff
Make typenames longer
Invent MIMEadapter's name in one place

and shorten it
Don't log password changes
Shorten template paths when used as names
Repair Debian requirements file
requirements_debian.txt: duplicate line
Add a config variable for running behind a proxy

and use Werkzeug's ProxyFix, not our own half-baked solution
Make default config vars overrideable
Fix root alias defaulting
Use relative paths for template sources
Don't override envvars (and analyze them correctly)
config_state may be stale