Convert projection table from reStructuredText to Markdown

doc/techref/index.md

@@ -8,6 +8,6 @@ visit the {gmt-docs}`GMT Technical Reference <reference.html>`.
 ```{toctree}
 :maxdepth: 1
 
-projections.rst
+projections.md
 encodings.md
 ```

doc/techref/projections.md

@@ -0,0 +1,9 @@
+# GMT Map Projections
+
+The table below shows the projection codes for the 31 GMT projections:
+
+| PyGMT Projection Argument | Projection Name |
+| --- | --- |
+| **A**lon<sub>0</sub>/lat<sub>0</sub>[/*horizon*]/*width* | [Lambert azimuthal equal area](https://www.pygmt.org/latest/projections/azim/azim_equidistant.html) |
+| **B**lon<sub>0</sub>/lat<sub>0</sub>/lat<sub>1</sub>/lat<sub>2</sub>/*width* | [Albers conic equal area](https://www.pygmt.org/latest/projections/conic/conic_albers.html) |
+| **C**lon<sub>0</sub>/lat<sub>0</sub>/*width* | [Cassini cylindrical](https://www.pygmt.org/latest/projections/cyl/cyl_cassini) |