DCW - added executable bit
DCW - added .gitignore
DCW - Start of work to add a main loop to secrets

Removed actions from usage docs.

Bumped version.

Now checks right at the start for the secrets file and prompts about
whether to create a new one.

Removed actions if statement.

read_secrets_from_file() now dies if the file doesn't exist.

Added TODO for Notes editing when you want to keep the entire existing
value.
DCW - Now prompts twice for new master password.

Added get_new_master_password() which loops for two matching non-blank
passwords.

read_secrets_from_file() back to old behaviour of just returning if the
secrets file doesn't exist.
DCW - Added mainloop() subroutine.

Currently just loops till quit.
DCW - get_new_master_password() now checks length.
DCW - NON BACKWARDS COMPATIBLE CHANGE

Global replace of password with passphrase. This includes the 'password'
field of the data hashes! An exiting secrets file won't work.

TODO check for and upgrade old files.
DCW - Code to upgrade secrets file to new format

mainloop() now checks the format of the secrets data structure and can
upgrade to latest format if desired.

mainloop() now checks how long it's been since the last time the master
passphrase was entered and will prompt for it again if required.

Added get_yes_or_no() which loops on a prompt till a yes or no is given.

Added is_current_format() which checks for the old format.

Added upgrade_secrets_file() which loads, upgrades, and saves secrets
file.
DCW - Added help to mainloop

This uses Pod::Usage, and I split the actions out into their own POD
section to make it clearer.
DCW - Added list_secrets() to list secrets

Plus moved most startup stuff into own scope.

Plus now checks for valid actions.
DCW - Bulk changes

POD for actions needing a name as well.

Added help, quit, and exit to valid actions.

Changed is_current_format() to load the secrets from disk.

Moved most of mainloop inside regex check of input.

Added add_secret() and edit_secret() functions.

Changed print_secret() to load the secrets from disk.

Removed uncalled get_secret_by_name() and get_secret_name().

get_secret_fields() no longer dies if the secret's password doesn't
match. Rather, it loops till they do.

list_secrets() now loads secrets from disk.
DCW - Fix POD for upgrade_secrets_file()
DCW - Changes file added. POD changes
DCW - README in line with script POD