Documentation improvements.

README.md

@@ -1,2 +1,5 @@
 # ngs
 Multiple go packages for working with next-generation sequencing (ngs).
+
+Each package has it's own README but there is a single CHANGELOG for the
+whole repo.

genome/genome.go

@@ -1,3 +1,5 @@
+// Package genome has types and functions for operating on genomics files
+// and data.
 package genome
 
 import (

gff3/gff3.go

@@ -1,3 +1,4 @@
+// Package gff3 has simple functions for operating on GFF3 files.
 package gff3
 
 import (

selector/README.md

@@ -1,13 +1,13 @@
 # selector
 
-A Selector is a string of the form operation:subject:pattern which can
+A Selector is a string of the form `operation:subject:pattern` which can
 be used to define select/filter operations on collections of records.
-
 For example, selectors that could be used with GFF3 records might look
 like:
-
-  keep:seqid:^GL
-  delete:type:.*_UTR
+```
+keep:seqid:^GL
+delete:type:.*_UTR
+```
 
 In general, the effect of all selectors is to drop records from some
 collection of records. Selectors with delete operations drop any record
@@ -20,12 +20,12 @@ pattern. Because delete only drops matching records, multiple delete
 selectors, applied sequentially, with tight patterns can be used to
 selectively prune away records that you don't wish to retain.
 
-In cases where multiple selectors are allowed, they shoudl probably be
+In cases where multiple selectors are allowed, they should probably be
 applied sequentially in the order in which they are specified on the
 command line, in the config file, etc.
 
-The colon character ':' must not be used in the subject, operation or
-pattern of a selector - it is strictly reserved as a separator for the
+The colon character ':' must not be used in the `operation`, `subject`,
+or pattern of a selector - it is strictly reserved as a separator for the
 selector. The package has no easy way to enforce this requirement so
 it's up to the user to watch for too many elements in a selector which
 might suggest improper use of the colon.

selector/selector.go

@@ -1,3 +1,7 @@
+// Package selector is a trivial set of helper methods for defining
+// operation:subject:pattern triples which can be used to describe
+// filtering operations on collections of records.
+// See the README.md for more details.
 package selector
 
 import (