Update 00_basic_tips.md

purged specific length of passwords (as those get obsolete very quick)
changed laptop to the more fitting word notebook
added some information to transport layer security
added section to at least mention modern measures like DNSSEC/DANE - needs to be improved
Update 01_types_of_email.md

adding specific keywords for email protocols, security targets
deleted an incomplete sentence.
added section on metadata
Merge pull request #109 from vv01f/master

Update 00_basic_tips.md
Merge remote-tracking branch 'upstream/master'