added spec_image, spec_hist, spec_boxplot and fixed some cran comments
diff --git a/man/spec_image.Rd b/man/spec_image.Rd
new file mode 100644
index 0000000..a4638e5
--- /dev/null
+++ b/man/spec_image.Rd
@@ -0,0 +1,24 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/spec_tools.R
+\name{spec_image}
+\alias{spec_image}
+\title{Setup image path, size, etc}
+\usage{
+spec_image(path, width, height, res = 300, svg_text = NULL)
+}
+\arguments{
+\item{path}{file path(s)}
+
+\item{width}{image width in pixel}
+
+\item{height}{image height in pixel}
+
+\item{res}{image resolution.}
+
+\item{svg_text}{If you have the raw text for SVG. Put them here}
+}
+\description{
+Users can directly provide image file path to column spec.
+However, if you need to specify the size of the image, you will need this
+function.
+}