add support for cisco spa100 family (spa112 and spa122)
fix whitespaces
enable echo canceling on spa family plugins
split spa.xml into spa-ata.xml and spa-phone.xml

preparing to change default values for ATA devices while leaving those of phone
devices untouched
Modify default parameters values

Most ATA are used to connect analog faxes. Parameters changed here ease
fax integration.
no need to specify the user-access (ua) attribute
remove some non-ATA parameters from spa-ata.xml

They don't hurt but they are not necessary.
put all ATA specific parameters near the end

Some parameters were duplicated.
add parameters for SPA100

It's not the same as for the other SPA.
Merge branch '5221-spa122'