lib: support 'personal' regexp, move to mu-contacts

Move the determination of "personal" to MuContacts; add support for
regexps (POSIX-basic, in //)

man/mu-init.1

@@ -1,4 +1,4 @@
-.TH MU-INIT 1 "February 2020" "User Manuals"
+.TH MU-INIT 1 "October 2020" "User Manuals"
 
 .SH NAME
 
@@ -10,13 +10,14 @@ mu init \- initialize the mu message database
 
 .SH DESCRIPTION
 
-\fBmu init\fR is the \fBmu\fR command for setting up the mu message
-database. After \fBmu init\fR has completed, you can run \fBmu index\fR
+\fBmu init\fR is the subcommand for setting up the mu message
+database. After \fBmu init\fR has completed, you can run \fBmu
+index\fR
 
 .SH OPTIONS
 
-Note, some of the general options are described in the \fBmu(1)\fR man-page and
-not here, as they apply to multiple mu commands.
+Note, some of the general options are described in the \fBmu(1)\fR
+man-page and not here, as they apply to multiple mu commands.
 
 .TP
 \fB\-\-muhome\fR
@@ -34,7 +35,6 @@ are not supported.
 
 .TP
 \fB\-\-my-address\fR=\fI<my-email-address>\fR
-
 specifies that some e-mail addresses are 'my-address' (\fB\-\-my-address\fR can
 be used multiple times). This is used by \fBmu cfind\fR -- any e-mail address
 found in the address fields of a message which also has \fI<my-email-address>\fR
@@ -42,6 +42,10 @@ in one of its address fields is considered a \fIpersonal\fR e-mail address. This
 allows you, for example, to filter out (\fBmu cfind --personal\fR) addresses
 which were merely seen in mailing list messages.
 
+\fI<my-email-address>\fR can be either a plain e-mail address (such as
+\fBfoo@example.com\fR), or a regular-expression (of the 'Basic POSIX'
+flavor), wrapped in \B/\fR (such as \B/foo-.*@example\\.com\fR).
+
 .SH ENVIRONMENT
 
 \fBmu init\fR uses \fBMAILDIR\fR to find the user's Maildir if it has not been