Update man page introduction to reflect modern samtools

doc/samtools.1

@@ -105,19 +105,19 @@ samtools depad input.bam
 
 .SH DESCRIPTION
 .PP
-Samtools is a set of utilities that manipulate alignments in the BAM
-format. It imports from and exports to the SAM (Sequence Alignment/Map)
-format, does sorting, merging and indexing, and allows to retrieve reads
-in any regions swiftly.
+Samtools is a set of utilities that manipulate alignments in the SAM
+(Sequence Alignment/Map), BAM, and CRAM formats.
+It converts between the formats, does sorting, merging and indexing,
+and can retrieve reads in any regions swiftly.
 
 Samtools is designed to work on a stream. It regards an input file `-'
 as the standard input (stdin) and an output file `-' as the standard
 output (stdout). Several commands can thus be combined with Unix
 pipes. Samtools always output warning and error messages to the standard
 error output (stderr).
 
-Samtools is also able to open a BAM (not SAM) file on a remote FTP or
-HTTP server if the BAM file name starts with `ftp://' or `http://'.
+Samtools is also able to open files on remote FTP or
+HTTP(S) servers if the file name starts with `ftp://', `http://', etc.
 Samtools checks the current working directory for the index file and
 will download the index upon absence. Samtools does not retrieve the
 entire alignment file unless it is asked to do so.