Update profiling.rst

There is some confusion about how to enable profiling for queries. This will save some time for devs who want to debug their generated SQL.
Update profiling.rst

correcting rst syntax
Merge pull request #3059 from manuganji/patch-1

Update profiling.rst
Fix #3057
fix callable hooks
fix callable hooks
Merge pull request #3065 from dtmax/develop

fix calling of callable hooks
A fix about loading language files - ensuring suffix '_lang' presence properly.
Merge pull request #3072 from ivantcholakov/develop

A fix about loading language files - ensuring suffix '_lang' presence properly.
[ci skip] Update changelog
Merge branch 'release/3.0' of CodeIgniter