Add features.md doc and link to it in the options page

The features.md doc describes all the features that the extension
provides. This change also adds a link to this doc in the options page
so it can be accessed quickly.

Fixes: #23
Change-Id: Iad1d54ba216d6dd4e7820fe2a2ed8644f86ed945
diff --git a/docs/resources/batch_lock.gif b/docs/resources/batch_lock.gif
new file mode 100644
index 0000000..d75974e
--- /dev/null
+++ b/docs/resources/batch_lock.gif
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diff --git a/docs/resources/compress_gif.bash b/docs/resources/compress_gif.bash
new file mode 100644
index 0000000..01cb969
--- /dev/null
+++ b/docs/resources/compress_gif.bash
@@ -0,0 +1,6 @@
+#!/bin/bash
+# Helper tool used to compress generated GIFs
+gifsicle -O3 --lossy=100 --colors 128 $1 -o $2
+
+# webp isn't yet allowed to be used in gitiles
+#gif2webp -mixed -min_size -loop_compatibility $2
diff --git a/docs/resources/compress_image.bash b/docs/resources/compress_image.bash
new file mode 100644
index 0000000..9369f64
--- /dev/null
+++ b/docs/resources/compress_image.bash
@@ -0,0 +1,3 @@
+#!/bin/bash
+# Helper tool used to compress screenshots from PNG to JPEG
+convert -quality 85 $1 $2
diff --git a/docs/resources/drag_and_drop_fix.gif b/docs/resources/drag_and_drop_fix.gif
new file mode 100644
index 0000000..3193f76
--- /dev/null
+++ b/docs/resources/drag_and_drop_fix.gif
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diff --git a/docs/resources/fix_toolbar.gif b/docs/resources/fix_toolbar.gif
new file mode 100644
index 0000000..769b592
--- /dev/null
+++ b/docs/resources/fix_toolbar.gif
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diff --git a/docs/resources/op_indicator_1.gif b/docs/resources/op_indicator_1.gif
new file mode 100644
index 0000000..464fc65
--- /dev/null
+++ b/docs/resources/op_indicator_1.gif
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diff --git a/docs/resources/op_indicator_2.gif b/docs/resources/op_indicator_2.gif
new file mode 100644
index 0000000..9280c74
--- /dev/null
+++ b/docs/resources/op_indicator_2.gif
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diff --git a/docs/resources/op_indicator_3.gif b/docs/resources/op_indicator_3.gif
new file mode 100644
index 0000000..64ec33b
--- /dev/null
+++ b/docs/resources/op_indicator_3.gif
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diff --git a/docs/resources/previous_posts.jpg b/docs/resources/previous_posts.jpg
new file mode 100644
index 0000000..d9616bd
--- /dev/null
+++ b/docs/resources/previous_posts.jpg
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diff --git a/docs/resources/sticky_headers.gif b/docs/resources/sticky_headers.gif
new file mode 100644
index 0000000..b7589cb
--- /dev/null
+++ b/docs/resources/sticky_headers.gif
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