fixes and improvements

exceptions related code needs work

Readme.md

@@ -1,11 +1,11 @@
 
 ### TODO
-- save table command
+- drop table command
 - move csv generation from usql(save_table) to table class
-- add exceptions
+- add exceptions and rename it to UsqlException
 - class members should have prefix m_
+- maybe to create iterator on table
 - add pipe | token
-- add to_date a to_string functions
-- add min and max functions, eg aggregate functions
+- add count min and max functions, eg aggregate functions
 - add logging
-- add const wherever should be
+- add const wherever should be