Fix messages with server-time not showing as new activity

Added a parameter to fe_print_text() to say that the message does not represent
new activity. This is used when a log from an old session is loaded. This used
to be implicit whenever the timestamp was non-zero, but with server-time this no
longer makes sense.

Fixes issue #746.
Remove left over ifdef for spellcheck
Add hexchat perl module to gitignore
Fix a few cppcheck warnings.

Use the proper data type in format functions and fix a resource leak.
Fix configure output when python disabled